Section 1: Tools of Geometry 

Coordinate Plane 
16:41 
 
Intro 
0:00  
 
The Coordinate System 
0:12  
 
 Coordinate Plane: Xaxis and Yaxis 
0:15  
 
 Quadrants 
1:02  
 
 Origin 
2:00  
 
 Ordered Pair 
2:17  
 
Coordinate Plane 
2:59  
 
 Example: Writing Coordinates 
3:01  
 
Coordinate Plane, cont. 
4:15  
 
 Example: Graphing & Coordinate Plane 
4:17  
 
 Collinear 
5:58  
 
Extra Example 1: Writing Coordinates & Quadrants 
7:34  
 
Extra Example 2: Quadrants 
8:52  
 
Extra Example 3: Graphing & Coordinate Plane 
10:58  
 
Extra Example 4: Collinear 
12:50  

Points, Lines and Planes 
17:17 
 
Intro 
0:00  
 
Points 
0:07  
 
 Definition and Example of Points 
0:09  
 
Lines 
0:50  
 
 Definition and Example of Lines 
0:51  
 
Planes 
2:59  
 
 Definition and Example of Planes 
3:00  
 
Drawing and Labeling 
4:40  
 
 Example 1: Drawing and Labeling 
4:41  
 
 Example 2: Drawing and Labeling 
5:54  
 
 Example 3: Drawing and Labeling 
6:41  
 
 Example 4: Drawing and Labeling 
8:23  
 
Extra Example 1: Points, Lines and Planes 
10:19  
 
Extra Example 2: Naming Figures 
11:16  
 
Extra Example 3: Points, Lines and Planes 
12:35  
 
Extra Example 4: Draw and Label 
14:44  

Measuring Segments 
31:31 
 
Intro 
0:00  
 
Segments 
0:06  
 
 Examples of Segments 
0:08  
 
Ruler Postulate 
1:30  
 
 Ruler Postulate 
1:31  
 
Segment Addition Postulate 
5:02  
 
 Example and Definition of Segment Addition Postulate 
5:03  
 
Segment Addition Postulate 
8:01  
 
 Example 1: Segment Addition Postulate 
8:04  
 
 Example 2: Segment Addition Postulate 
11:15  
 
Pythagorean Theorem 
12:36  
 
 Definition of Pythagorean Theorem 
12:37  
 
Pythagorean Theorem, cont. 
15:49  
 
 Example: Pythagorean Theorem 
15:50  
 
Distance Formula 
16:48  
 
 Example and Definition of Distance Formula 
16:49  
 
Extra Example 1: Find Each Measure 
20:32  
 
Extra Example 2: Find the Missing Measure 
22:11  
 
Extra Example 3: Find the Distance Between the Two Points 
25:36  
 
Extra Example 4: Pythagorean Theorem 
29:33  

Midpoints and Segment Congruence 
42:26 
 
Intro 
0:00  
 
Definition of Midpoint 
0:07  
 
 Midpoint 
0:10  
 
Midpoint Formulas 
1:30  
 
 Midpoint Formula: On a Number Line 
1:45  
 
 Midpoint Formula: In a Coordinate Plane 
2:50  
 
Midpoint 
4:40  
 
 Example: Midpoint on a Number Line 
4:43  
 
Midpoint 
6:05  
 
 Example: Midpoint in a Coordinate Plane 
6:06  
 
Midpoint 
8:28  
 
 Example 1 
8:30  
 
 Example 2 
13:01  
 
Segment Bisector 
15:14  
 
 Definition and Example of Segment Bisector 
15:15  
 
Proofs 
17:27  
 
 Theorem 
17:53  
 
 Proof 
18:21  
 
Midpoint Theorem 
19:37  
 
 Example: Proof & Midpoint Theorem 
19:38  
 
Extra Example 1: Midpoint on a Number Line 
23:44  
 
Extra Example 2: Drawing Diagrams 
26:25  
 
Extra Example 3: Midpoint 
29:14  
 
Extra Example 4: Segment Bisector 
33:21  

Angles 
42:34 
 
Intro 
0:00  
 
Angles 
0:05  
 
 Angle 
0:07  
 
 Ray 
0:23  
 
 Opposite Rays 
2:09  
 
Angles 
3:22  
 
 Example: Naming Angle 
3:23  
 
Angles 
6:39  
 
 Interior, Exterior, Angle 
6:40  
 
 Measure and Degrees 
7:38  
 
Protractor Postulate 
8:37  
 
 Example: Protractor Postulate 
8:38  
 
Angle Addition Postulate 
11:41  
 
 Example: Angle addition Postulate 
11:42  
 
Classifying Angles 
14:10  
 
 Acute Angle 
14:16  
 
 Right Angles 
14:30  
 
 Obtuse Angle 
14:41  
 
Angle Bisector 
15:02  
 
 Example: Angle Bisector 
15:04  
 
Angle Relationships 
16:43  
 
 Adjacent Angles 
16:47  
 
 Vertical Angles 
17:49  
 
 Linear Pair 
19:40  
 
Angle Relationships 
20:31  
 
 Right Angles 
20:32  
 
 Supplementary Angles 
21:15  
 
 Complementary Angles 
21:33  
 
Extra Example 1: Angles 
24:08  
 
Extra Example 2: Angles 
29:06  
 
Extra Example 3: Angles 
32:05  
 
Extra Example 4 Angles 
35:44  
Section 2: Reasoning & Proof 

Inductive Reasoning 
19:00 
 
Intro 
0:00  
 
Inductive Reasoning 
0:05  
 
 Conjecture 
0:06  
 
 Inductive Reasoning 
0:15  
 
Examples 
0:55  
 
 Example: Sequence 
0:56  
 
 More Example: Sequence 
2:00  
 
Using Inductive Reasoning 
2:50  
 
 Example: Conjecture 
2:51  
 
 More Example: Conjecture 
3:48  
 
Counterexamples 
4:56  
 
 Counterexample 
4:58  
 
Extra Example 1: Conjecture 
6:59  
 
Extra Example 2: Sequence and Pattern 
10:20  
 
Extra Example 3: Inductive Reasoning 
12:46  
 
Extra Example 4: Conjecture and Counterexample 
15:17  

Conditional Statements 
42:47 
 
Intro 
0:00  
 
If Then Statements 
0:05  
 
 If Then Statements 
0:06  
 
Other Forms 
2:29  
 
 Example: Without Then 
2:40  
 
 Example: Using When 
3:03  
 
 Example: Hypothesis 
3:24  
 
Identify the Hypothesis and Conclusion 
3:52  
 
 Example 1: Hypothesis and Conclusion 
3:58  
 
 Example 2: Hypothesis and Conclusion 
4:31  
 
 Example 3: Hypothesis and Conclusion 
5:38  
 
Write in If Then Form 
6:16  
 
 Example 1: Write in If Then Form 
6:23  
 
 Example 2: Write in If Then Form 
6:57  
 
 Example 3: Write in If Then Form 
7:39  
 
Other Statements 
8:40  
 
 Other Statements 
8:41  
 
Converse Statements 
9:18  
 
 Converse Statements 
9:20  
 
Converses and Counterexamples 
11:04  
 
 Converses and Counterexamples 
11:05  
 
 Example 1: Converses and Counterexamples 
12:02  
 
 Example 2: Converses and Counterexamples 
15:10  
 
 Example 3: Converses and Counterexamples 
17:08  
 
Inverse Statement 
19:58  
 
 Definition and Example 
19:59  
 
Inverse Statement 
21:46  
 
 Example 1: Inverse and Counterexample 
21:47  
 
 Example 2: Inverse and Counterexample 
23:34  
 
Contrapositive Statement 
25:20  
 
 Definition and Example 
25:21  
 
Contrapositive Statement 
26:58  
 
 Example: Contrapositive Statement 
27:00  
 
Summary 
29:03  
 
 Summary of Lesson 
29:04  
 
Extra Example 1: Hypothesis and Conclusion 
32:20  
 
Extra Example 2: IfThen Form 
33:23  
 
Extra Example 3: Converse, Inverse, and Contrapositive 
34:54  
 
Extra Example 4: Converse, Inverse, and Contrapositive 
37:56  

Point, Line, and Plane Postulates 
17:24 
 
Intro 
0:00  
 
What are Postulates? 
0:09  
 
 Definition of Postulates 
0:10  
 
Postulates 
1:22  
 
 Postulate 1: Two Points 
1:23  
 
 Postulate 2: Three Points 
2:02  
 
 Postulate 3: Line 
2:45  
 
Postulates, cont.. 
3:08  
 
 Postulate 4: Plane 
3:09  
 
 Postulate 5: Two Points in a Plane 
3:53  
 
Postulates, cont.. 
4:46  
 
 Postulate 6: Two Lines Intersect 
4:47  
 
 Postulate 7: Two Plane Intersect 
5:28  
 
Using the Postulates 
6:34  
 
 Examples: True or False 
6:35  
 
Using the Postulates 
10:18  
 
 Examples: True or False 
10:19  
 
Extra Example 1: Always, Sometimes, or Never 
12:22  
 
Extra Example 2: Always, Sometimes, or Never 
13:15  
 
Extra Example 3: Always, Sometimes, or Never 
14:16  
 
Extra Example 4: Always, Sometimes, or Never 
15:03  

Deductive Reasoning 
36:03 
 
Intro 
0:00  
 
Deductive Reasoning 
0:06  
 
 Definition of Deductive Reasoning 
0:07  
 
Inductive vs. Deductive 
2:51  
 
 Inductive Reasoning 
2:52  
 
 Deductive reasoning 
3:19  
 
Law of Detachment 
3:47  
 
 Law of Detachment 
3:48  
 
 Examples of Law of Detachment 
4:31  
 
Law of Syllogism 
7:32  
 
 Law of Syllogism 
7:33  
 
 Example 1: Making a Conclusion 
9:02  
 
 Example 2: Making a Conclusion 
12:54  
 
Using Laws of Logic 
14:12  
 
 Example 1: Determine the Logic 
14:42  
 
 Example 2: Determine the Logic 
17:02  
 
Using Laws of Logic, cont. 
18:47  
 
 Example 3: Determine the Logic 
19:03  
 
 Example 4: Determine the Logic 
20:56  
 
Extra Example 1: Determine the Conclusion and Law 
22:12  
 
Extra Example 2: Determine the Conclusion and Law 
25:39  
 
Extra Example 3: Determine the Logic and Law 
29:50  
 
Extra Example 4: Determine the Logic and Law 
31:27  

Proofs in Algebra: Properties of Equality 
44:31 
 
Intro 
0:00  
 
Properties of Equality 
0:10  
 
 Addition Property of Equality 
0:28  
 
 Subtraction Property of Equality 
1:10  
 
 Multiplication Property of Equality 
1:41  
 
 Division Property of Equality 
1:55  
 
 Addition Property of Equality Using Angles 
2:46  
 
Properties of Equality, cont. 
4:10  
 
 Reflexive Property of Equality 
4:11  
 
 Symmetric Property of Equality 
5:24  
 
 Transitive Property of Equality 
6:10  
 
Properties of Equality, cont. 
7:04  
 
 Substitution Property of Equality 
7:05  
 
 Distributive Property of Equality 
8:34  
 
Two Column Proof 
9:40  
 
 Example: Two Column Proof 
9:46  
 
Proof Example 1 
16:13  
 
Proof Example 2 
23:49  
 
Proof Example 3 
30:33  
 
Extra Example 1: Name the Property of Equality 
38:07  
 
Extra Example 2: Name the Property of Equality 
40:16  
 
Extra Example 3: Name the Property of Equality 
41:35  
 
Extra Example 4: Name the Property of Equality 
43:02  

Proving Segment Relationship 
41:02 
 
Intro 
0:00  
 
Good Proofs 
0:12  
 
 Five Essential Parts 
0:13  
 
Proof Reasons 
1:38  
 
 Undefined 
1:40  
 
 Definitions 
2:06  
 
 Postulates 
2:42  
 
 Previously Proven Theorems 
3:24  
 
Congruence of Segments 
4:10  
 
 Theorem: Congruence of Segments 
4:12  
 
Proof Example 
10:16  
 
 Proof: Congruence of Segments 
10:17  
 
Setting Up Proofs 
19:13  
 
 Example: Two Segments with Equal Measures 
19:15  
 
Setting Up Proofs 
21:48  
 
 Example: Vertical Angles are Congruent 
21:50  
 
Setting Up Proofs 
23:59  
 
 Example: Segment of a Triangle 
24:00  
 
Extra Example 1: Congruence of Segments 
27:03  
 
Extra Example 2: Setting Up Proofs 
28:50  
 
Extra Example 3: Setting Up Proofs 
30:55  
 
Extra Example 4: TwoColumn Proof 
33:11  

Proving Angle Relationships 
33:37 
 
Intro 
0:00  
 
Supplement Theorem 
0:05  
 
 Supplementary Angles 
0:06  
 
Congruence of Angles 
2:37  
 
 Proof: Congruence of Angles 
2:38  
 
Angle Theorems 
6:54  
 
 Angle Theorem 1: Supplementary Angles 
6:55  
 
 Angle Theorem 2: Complementary Angles 
10:25  
 
Angle Theorems 
11:32  
 
 Angle Theorem 3: Right Angles 
11:35  
 
 Angle Theorem 4: Vertical Angles 
12:09  
 
 Angle Theorem 5: Perpendicular Lines 
12:57  
 
Using Angle Theorems 
13:45  
 
 Example 1: Always, Sometimes, or Never 
13:50  
 
 Example 2: Always, Sometimes, or Never 
14:28  
 
 Example 3: Always, Sometimes, or Never 
16:21  
 
Extra Example 1: Always, Sometimes, or Never 
16:53  
 
Extra Example 2: Find the Measure of Each Angle 
18:55  
 
Extra Example 3: Find the Measure of Each Angle 
25:03  
 
Extra Example 4: TwoColumn Proof 
27:08  
Section 3: Perpendicular & Parallel Lines 

Parallel Lines and Transversals 
37:35 
 
Intro 
0:00  
 
Lines 
0:06  
 
 Parallel Lines 
0:09  
 
 Skew Lines 
2:02  
 
 Transversal 
3:42  
 
Angles Formed by a Transversal 
4:28  
 
 Interior Angles 
5:53  
 
 Exterior Angles 
6:09  
 
 Consecutive Interior Angles 
7:04  
 
 Alternate Exterior Angles 
9:47  
 
 Alternate Interior Angles 
11:22  
 
 Corresponding Angles 
12:27  
 
Angles Formed by a Transversal 
15:29  
 
 Relationship Between Angles 
15:30  
 
Extra Example 1: Intersecting, Parallel, or Skew 
19:26  
 
Extra Example 2: Draw a Diagram 
21:37  
 
Extra Example 3: Name the Figures 
24:12  
 
Extra Example 4: Angles Formed by a Transversal 
28:38  

Angles and Parallel Lines 
41:53 
 
Intro 
0:00  
 
Corresponding Angles Postulate 
0:05  
 
 Corresponding Angles Postulate 
0:06  
 
Alternate Interior Angles Theorem 
3:05  
 
 Alternate Interior Angles Theorem 
3:07  
 
Consecutive Interior Angles Theorem 
5:16  
 
 Consecutive Interior Angles Theorem 
5:17  
 
Alternate Exterior Angles Theorem 
6:42  
 
 Alternate Exterior Angles Theorem 
6:43  
 
Parallel Lines Cut by a Transversal 
7:18  
 
 Example: Parallel Lines Cut by a Transversal 
7:19  
 
Perpendicular Transversal Theorem 
14:54  
 
 Perpendicular Transversal Theorem 
14:55  
 
Extra Example 1: State the Postulate or Theorem 
16:37  
 
Extra Example 2: Find the Measure of the Numbered Angle 
18:53  
 
Extra Example 3: Find the Measure of Each Angle 
25:13  
 
Extra Example 4: Find the Values of x, y, and z 
36:26  

Slope of Lines 
44:06 
 
Intro 
0:00  
 
Definition of Slope 
0:06  
 
 Slope Equation 
0:13  
 
Slope of a Line 
3:45  
 
 Example: Find the Slope of a Line 
3:47  
 
Slope of a Line 
8:38  
 
 More Example: Find the Slope of a Line 
8:40  
 
Slope Postulates 
12:32  
 
 Proving Slope Postulates 
12:33  
 
Parallel or Perpendicular Lines 
17:23  
 
 Example: Parallel or Perpendicular Lines 
17:24  
 
Using Slope Formula 
20:02  
 
 Example: Using Slope Formula 
20:03  
 
Extra Example 1: Slope of a Line 
25:10  
 
Extra Example 2: Slope of a Line 
26:31  
 
Extra Example 3: Graph the Line 
34:11  
 
Extra Example 4: Using the Slope Formula 
38:50  

Proving Lines Parallel 
25:55 
 
Intro 
0:00  
 
Postulates 
0:06  
 
 Postulate 1: Parallel Lines 
0:21  
 
 Postulate 2: Parallel Lines 
2:16  
 
Parallel Postulate 
3:28  
 
 Definition and Example of Parallel Postulate 
3:29  
 
Theorems 
4:29  
 
 Theorem 1: Parallel Lines 
4:40  
 
 Theorem 2: Parallel Lines 
5:37  
 
Theorems, cont. 
6:10  
 
 Theorem 3: Parallel Lines 
6:11  
 
Extra Example 1: Determine Parallel Lines 
6:56  
 
Extra Example 2: Find the Value of x 
11:42  
 
Extra Example 3: Opposite Sides are Parallel 
14:48  
 
Extra Example 4: Proving Parallel Lines 
20:42  

Parallels and Distance 
19:48 
 
Intro 
0:00  
 
Distance Between a Points and Line 
0:07  
 
 Definition and Example 
0:08  
 
Distance Between Parallel Lines 
1:51  
 
 Definition and Example 
1:52  
 
Extra Example 1: Drawing a Segment to Represent Distance 
3:02  
 
Extra Example 2: Drawing a Segment to Represent Distance 
4:27  
 
Extra Example 3: Graph, Plot, and Construct a Perpendicular Segment 
5:13  
 
Extra Example 4: Distance Between Two Parallel Lines 
15:37  
Section 4: Congruent Triangles 

Classifying Triangles 
28:43 
 
Intro 
0:00  
 
Triangles 
0:09  
 
 Triangle: A ThreeSided Polygon 
0:10  
 
 Sides 
1:00  
 
 Vertices 
1:22  
 
 Angles 
1:56  
 
Classifying Triangles by Angles 
2:59  
 
 Acute Triangle 
3:19  
 
 Obtuse Triangle 
4:08  
 
 Right Triangle 
4:44  
 
Equiangular Triangle 
5:38  
 
 Definition and Example of an Equiangular Triangle 
5:39  
 
Classifying Triangles by Sides 
6:57  
 
 Scalene Triangle 
7:17  
 
 Isosceles Triangle 
7:57  
 
 Equilateral Triangle 
8:12  
 
Isosceles Triangle 
8:58  
 
 Labeling Isosceles Triangle 
9:00  
 
 Labeling Right Triangle 
10:44  
 
Isosceles Triangle 
11:10  
 
 Example: Find x, AB, BC, and AC 
11:11  
 
Extra Example 1: Classify Each Triangle 
13:45  
 
Extra Example 2: Always, Sometimes, or Never 
16:28  
 
Extra Example 3: Find All the Sides of the Isosceles Triangle 
20:29  
 
Extra Example 4: Distance Formula and Triangle 
22:29  

Measuring Angles in Triangles 
44:43 
 
Intro 
0:00  
 
Angle Sum Theorem 
0:09  
 
 Angle Sum Theorem for Triangle 
0:11  
 
Using Angle Sum Theorem 
4:06  
 
 Find the Measure of the Missing Angle 
4:07  
 
Third Angle Theorem 
4:58  
 
 Example: Third Angle Theorem 
4:59  
 
Exterior Angle Theorem 
7:58  
 
 Example: Exterior Angle Theorem 
8:00  
 
Flow Proof of Exterior Angle Theorem 
15:14  
 
 Flow Proof of Exterior Angle Theorem 
15:17  
 
Triangle Corollaries 
27:21  
 
 Triangle Corollary 1 
27:50  
 
 Triangle Corollary 2 
30:42  
 
Extra Example 1: Find the Value of x 
32:55  
 
Extra Example 2: Find the Value of x 
34:20  
 
Extra Example 3: Find the Measure of the Angle 
35:38  
 
Extra Example 4: Find the Measure of Each Numbered Angle 
39:00  

Exploring Congruent Triangles 
26:46 
 
Intro 
0:00  
 
Congruent Triangles 
0:15  
 
 Example of Congruent Triangles 
0:17  
 
Corresponding Parts 
3:39  
 
 Corresponding Angles and Sides of Triangles 
3:40  
 
Definition of Congruent Triangles 
11:24  
 
 Definition of Congruent Triangles 
11:25  
 
Triangle Congruence 
16:37  
 
 Congruence of Triangles 
16:38  
 
Extra Example 1: Congruence Statement 
18:24  
 
Extra Example 2: Congruence Statement 
21:26  
 
Extra Example 3: Draw and Label the Figure 
23:09  
 
Extra Example 4: Drawing Triangles 
24:04  

Proving Triangles Congruent 
47:51 
 
Intro 
0:00  
 
SSS Postulate 
0:18  
 
 SideSideSide Postulate 
0:27  
 
SAS Postulate 
2:26  
 
 SideAngleSide Postulate 
2:29  
 
SAS Postulate 
3:57  
 
 Proof Example 
3:58  
 
ASA Postulate 
11:47  
 
 AngleSideAngle Postulate 
11:53  
 
AAS Theorem 
14:13  
 
 AngleAngleSide Theorem 
14:14  
 
Methods Overview 
16:16  
 
 Methods Overview 
16:17  
 
 SSS 
16:33  
 
 SAS 
17:06  
 
 ASA 
17:50  
 
 AAS 
18:17  
 
 CPCTC 
19:14  
 
Extra Example 1:Proving Triangles are Congruent 
21:29  
 
Extra Example 2: Proof 
25:40  
 
Extra Example 3: Proof 
30:41  
 
Extra Example 4: Proof 
38:41  

Isosceles and Equilateral Triangles 
27:53 
 
Intro 
0:00  
 
Isosceles Triangle Theorem 
0:07  
 
 Isosceles Triangle Theorem 
0:09  
 
Isosceles Triangle Theorem 
2:26  
 
 Example: Using the Isosceles Triangle Theorem 
2:27  
 
Isosceles Triangle Theorem Converse 
3:29  
 
 Isosceles Triangle Theorem Converse 
3:30  
 
Equilateral Triangle Theorem Corollaries 
4:30  
 
 Equilateral Triangle Theorem Corollary 1 
4:59  
 
 Equilateral Triangle Theorem Corollary 2 
5:55  
 
Extra Example 1: Find the Value of x 
7:08  
 
Extra Example 2: Find the Value of x 
10:04  
 
Extra Example 3: Proof 
14:04  
 
Extra Example 4: Proof 
22:41  
Section 5: Triangle Inequalities 

Special Segments in Triangles 
43:44 
 
Intro 
0:00  
 
Perpendicular Bisector 
0:06  
 
 Perpendicular Bisector 
0:07  
 
Perpendicular Bisector 
4:07  
 
 Perpendicular Bisector Theorems 
4:08  
 
Median 
6:30  
 
 Definition of Median 
6:31  
 
Median 
9:41  
 
 Example: Median 
9:42  
 
Altitude 
12:22  
 
 Definition of Altitude 
12:23  
 
Angle Bisector 
14:33  
 
 Definition of Angle Bisector 
14:34  
 
Angle Bisector 
16:41  
 
 Angle Bisector Theorems 
16:42  
 
Special Segments Overview 
18:57  
 
 Perpendicular Bisector 
19:04  
 
 Median 
19:32  
 
 Altitude 
19:49  
 
 Angle Bisector 
20:02  
 
 Examples: Special Segments 
20:18  
 
Extra Example 1: Draw and Label 
22:36  
 
Extra Example 2: Draw the Altitudes for Each Triangle 
24:37  
 
Extra Example 3: Perpendicular Bisector 
27:57  
 
Extra Example 4: Draw, Label, and Write Proof 
34:33  

Right Triangles 
26:34 
 
Intro 
0:00  
 
LL Theorem 
0:21  
 
 LegLeg Theorem 
0:25  
 
HA Theorem 
2:23  
 
 HypotenuseAngle Theorem 
2:24  
 
LA Theorem 
4:49  
 
 LegAngle Theorem 
4:50  
 
LA Theorem 
6:18  
 
 Example: Find x and y 
6:19  
 
HL Postulate 
8:22  
 
 HypotenuseLeg Postulate 
8:23  
 
Extra Example 1: LA Theorem & HL Postulate 
10:57  
 
Extra Example 2: Find x So That Each Pair of Triangles is Congruent 
14:15  
 
Extra Example 3: Twocolumn Proof 
17:02  
 
Extra Example 4: Twocolumn Proof 
21:01  

Indirect Proofs and Inequalities 
33:30 
 
Intro 
0:00  
 
Writing an Indirect Proof 
0:09  
 
 Step 1 
0:49  
 
 Step 2 
2:32  
 
 Step 3 
3:00  
 
Indirect Proof 
4:30  
 
 Example: 2 + 6 = 8 
5:00  
 
 Example: The Suspect is Guilty 
5:40  
 
 Example: Measure of Angle A < Measure of Angle B 
6:06  
 
Definition of Inequality 
7:47  
 
 Definition of Inequality & Example 
7:48  
 
Properties of Inequality 
9:55  
 
 Comparison Property 
9:58  
 
 Transitive Property 
10:33  
 
 Addition and Subtraction Properties 
12:01  
 
 Multiplication and Division Properties 
13:07  
 
Exterior Angle Inequality Theorem 
14:12  
 
 Example: Exterior Angle Inequality Theorem 
14:13  
 
Extra Example 1: Draw a Diagram for the Statement 
18:32  
 
Extra Example 2: Name the Property for Each Statement 
19:56  
 
Extra Example 3: State the Assumption 
21:22  
 
Extra Example 4: Write an Indirect Proof 
25:39  

Inequalities for Sides and Angles of a Triangle 
17:26 
 
Intro 
0:00  
 
Side to Angles 
0:10  
 
 If One Side of a Triangle is Longer Than Another Side 
0:11  
 
Converse: Angles to Sides 
1:57  
 
 If One Angle of a Triangle Has a Greater Measure Than Another Angle 
1:58  
 
Extra Example 1: Name the Angles in the Triangle From Least to Greatest 
2:38  
 
Extra Example 2: Find the Longest and Shortest Segment in the Triangle 
3:47  
 
Extra Example 3: Angles and Sides of a Triangle 
4:51  
 
Extra Example 4: Twocolumn Proof 
9:08  

Triangle Inequality 
28:11 
 
Intro 
0:00  
 
Triangle Inequality Theorem 
0:05  
 
 Triangle Inequality Theorem 
0:06  
 
Triangle Inequality Theorem 
4:22  
 
 Example 1: Triangle Inequality Theorem 
4:23  
 
 Example 2: Triangle Inequality Theorem 
9:40  
 
Extra Example 1: Determine if the Three Numbers can Represent the Sides of a Triangle 
12:00  
 
Extra Example 2: Finding the Third Side of a Triangle 
13:34  
 
Extra Example 3: Always True, Sometimes True, or Never True 
18:18  
 
Extra Example 4: Triangle and Vertices 
22:36  

Inequalities Involving Two Triangles 
29:36 
 
Intro 
0:00  
 
SAS Inequality Theorem 
0:06  
 
 SAS Inequality Theorem & Example 
0:25  
 
SSS Inequality Theorem 
4:33  
 
 SSS Inequality Theorem & Example 
4:34  
 
Extra Example 1: Write an Inequality Comparing the Segments 
6:08  
 
Extra Example 2: Determine if the Statement is True 
9:52  
 
Extra Example 3: Write an Inequality for x 
14:20  
 
Extra Example 4: Twocolumn Proof 
17:44  
Section 6: Quadrilaterals 

Parallelograms 
29:11 
 
Intro 
0:00  
 
Quadrilaterals 
0:06  
 
 Foursided Polygons 
0:08  
 
 Non Examples of Quadrilaterals 
0:47  
 
Parallelograms 
1:35  
 
 Parallelograms 
1:36  
 
Properties of Parallelograms 
4:28  
 
 Opposite Sides of a Parallelogram are Congruent 
4:29  
 
 Opposite Angles of a Parallelogram are Congruent 
5:49  
 
Angles and Diagonals 
6:24  
 
 Consecutive Angles in a Parallelogram are Supplementary 
6:25  
 
 The Diagonals of a Parallelogram Bisect Each Other 
8:42  
 
Extra Example 1: Complete Each Statement About the Parallelogram 
10:26  
 
Extra Example 2: Find the Values of x, y, and z of the Parallelogram 
13:21  
 
Extra Example 3: Find the Distance of Each Side to Verify the Parallelogram 
16:35  
 
Extra Example 4: Slope of Parallelogram 
23:15  

Proving Parallelograms 
42:43 
 
Intro 
0:00  
 
Parallelogram Theorems 
0:09  
 
 Theorem 1 
0:20  
 
 Theorem 2 
1:50  
 
Parallelogram Theorems, Cont. 
3:10  
 
 Theorem 3 
3:11  
 
 Theorem 4 
4:15  
 
Proving Parallelogram 
6:21  
 
 Example: Determine if Quadrilateral ABCD is a Parallelogram 
6:22  
 
Summary 
14:01  
 
 Both Pairs of Opposite Sides are Parallel 
14:14  
 
 Both Pairs of Opposite Sides are Congruent 
15:09  
 
 Both Pairs of Opposite Angles are Congruent 
15:24  
 
 Diagonals Bisect Each Other 
15:44  
 
 A Pair of Opposite Sides is Both Parallel and Congruent 
16:13  
 
Extra Example 1: Determine if Each Quadrilateral is a Parallelogram 
16:54  
 
Extra Example 2: Find the Value of x and y 
20:23  
 
Extra Example 3: Determine if the Quadrilateral ABCD is a Parallelogram 
24:05  
 
Extra Example 4: Twocolumn Proof 
30:28  

Rectangles 
29:47 
 
Intro 
0:00  
 
Rectangles 
0:03  
 
 Definition of Rectangles 
0:04  
 
Diagonals of Rectangles 
2:52  
 
 Rectangles: Diagonals Property 1 
2:53  
 
 Rectangles: Diagonals Property 2 
3:30  
 
Proving a Rectangle 
4:40  
 
 Example: Determine Whether Parallelogram ABCD is a Rectangle 
4:41  
 
Rectangles Summary 
9:22  
 
 Opposite Sides are Congruent and Parallel 
9:40  
 
 Opposite Angles are Congruent 
9:51  
 
 Consecutive Angles are Supplementary 
9:58  
 
 Diagonals are Congruent and Bisect Each Other 
10:05  
 
 All Four Angles are Right Angles 
10:40  
 
Extra Example 1: Find the Value of x 
11:03  
 
Extra Example 2: Name All Congruent Sides and Angles 
13:52  
 
Extra Example 3: Always, Sometimes, or Never True 
19:39  
 
Extra Example 4: Determine if ABCD is a Rectangle 
26:45  

Squares and Rhombi 
39:14 
 
Intro 
0:00  
 
Rhombus 
0:09  
 
 Definition of a Rhombus 
0:10  
 
Diagonals of a Rhombus 
2:03  
 
 Rhombus: Diagonals Property 1 
2:21  
 
 Rhombus: Diagonals Property 2 
3:49  
 
 Rhombus: Diagonals Property 3 
4:36  
 
Rhombus 
6:17  
 
 Example: Use the Rhombus to Find the Missing Value 
6:18  
 
Square 
8:17  
 
 Definition of a Square 
8:20  
 
Summary Chart 
11:06  
 
 Parallelogram 
11:07  
 
 Rectangle 
12:56  
 
 Rhombus 
13:54  
 
 Square 
14:44  
 
Extra Example 1: Diagonal Property 
15:44  
 
Extra Example 2: Use Rhombus ABCD to Find the Missing Value 
19:39  
 
Extra Example 3: Always, Sometimes, or Never True 
23:06  
 
Extra Example 4: Determine the Quadrilateral 
28:02  

Trapezoids and Kites 
30:48 
 
Intro 
0:00  
 
Trapezoid 
0:10  
 
 Definition of Trapezoid 
0:12  
 
Isosceles Trapezoid 
2:57  
 
 Base Angles of an Isosceles Trapezoid 
2:58  
 
 Diagonals of an Isosceles Trapezoid 
4:05  
 
Median of a Trapezoid 
4:26  
 
 Median of a Trapezoid 
4:27  
 
Median of a Trapezoid 
6:41  
 
 Median Formula 
7:00  
 
Kite 
8:28  
 
 Definition of a Kite 
8:29  
 
Quadrilaterals Summary 
11:19  
 
 A Quadrilateral with Two Pairs of Adjacent Congruent Sides 
11:20  
 
Extra Example 1: Isosceles Trapezoid 
14:50  
 
Extra Example 2: Median of Trapezoid 
18:28  
 
Extra Example 3: Always, Sometimes, or Never 
24:13  
 
Extra Example 4: Determine if the Figure is a Trapezoid 
26:49  
Section 7: Proportions and Similarity 

Using Proportions and Ratios 
20:10 
 
Intro 
0:00  
 
Ratio 
0:05  
 
 Definition and Examples of Writing Ratio 
0:06  
 
Proportion 
2:05  
 
 Definition of Proportion 
2:06  
 
 Examples of Proportion 
2:29  
 
Using Ratio 
5:53  
 
 Example: Ratio 
5:54  
 
Extra Example 1: Find Three Ratios Equivalent to 2/5 
9:28  
 
Extra Example 2: Proportion and Cross Products 
10:32  
 
Extra Example 3: Express Each Ratio as a Fraction 
13:18  
 
Extra Example 4: Fin the Measure of a 3:4:5 Triangle 
17:26  

Similar Polygons 
27:53 
 
Intro 
0:00  
 
Similar Polygons 
0:05  
 
 Definition of Similar Polygons 
0:06  
 
 Example of Similar Polygons 
2:32  
 
Scale Factor 
4:26  
 
 Scale Factor: Definition and Example 
4:27  
 
Extra Example 1: Determine if Each Pair of Figures is Similar 
7:03  
 
Extra Example 2: Find the Values of x and y 
11:33  
 
Extra Example 3: Similar Triangles 
19:57  
 
Extra Example 4: Draw Two Similar Figures 
23:36  

Similar Triangles 
34:10 
 
Intro 
0:00  
 
AA Similarity 
0:10  
 
 Definition of AA Similarity 
0:20  
 
 Example of AA Similarity 
2:32  
 
SSS Similarity 
4:46  
 
 Definition of SSS Similarity 
4:47  
 
 Example of SSS Similarity 
6:00  
 
SAS Similarity 
8:04  
 
 Definition of SAS Similarity 
8:05  
 
 Example of SAS Similarity 
9:12  
 
Extra Example 1: Determine Whether Each Pair of Triangles is Similar 
10:59  
 
Extra Example 2: Determine Which Triangles are Similar 
16:08  
 
Extra Example 3: Determine if the Statement is True or False 
23:11  
 
Extra Example 4: Write TwoColumn Proof 
26:25  

Parallel Lines and Proportional Parts 
24:07 
 
Intro 
0:00  
 
Triangle Proportionality 
0:07  
 
 Definition of Triangle Proportionality 
0:08  
 
 Example of Triangle Proportionality 
0:51  
 
Triangle Proportionality Converse 
2:19  
 
 Triangle Proportionality Converse 
2:20  
 
Triangle Midsegment 
3:42  
 
 Triangle Midsegment: Definition and Example 
3:43  
 
Parallel Lines and Transversal 
6:51  
 
 Parallel Lines and Transversal 
6:52  
 
Extra Example 1: Complete Each Statement 
8:59  
 
Extra Example 2: Determine if the Statement is True or False 
12:28  
 
Extra Example 3: Find the Value of x and y 
15:35  
 
Extra Example 4: Find Midpoints of a Triangle 
20:43  

Parts of Similar Triangles 
27:06 
 
Intro 
0:00  
 
Proportional Perimeters 
0:09  
 
 Proportional Perimeters: Definition and Example 
0:10  
 
Similar Altitudes 
2:23  
 
 Similar Altitudes: Definition and Example 
2:24  
 
Similar Angle Bisectors 
4:50  
 
 Similar Angle Bisectors: Definition and Example 
4:51  
 
Similar Medians 
6:05  
 
 Similar Medians: Definition and Example 
6:06  
 
Angle Bisector Theorem 
7:33  
 
 Angle Bisector Theorem 
7:34  
 
Extra Example 1: Parts of Similar Triangles 
10:52  
 
Extra Example 2: Parts of Similar Triangles 
14:57  
 
Extra Example 3: Parts of Similar Triangles 
19:27  
 
Extra Example 4: Find the Perimeter of Triangle ABC 
23:14  
Section 8: Applying Right Triangles & Trigonometry 

Pythagorean Theorem 
21:14 
 
Intro 
0:00  
 
Pythagorean Theorem 
0:05  
 
 Pythagorean Theorem & Example 
0:06  
 
Pythagorean Converse 
1:20  
 
 Pythagorean Converse & Example 
1:21  
 
Pythagorean Triple 
2:42  
 
 Pythagorean Triple 
2:43  
 
Extra Example 1: Find the Missing Side 
4:59  
 
Extra Example 2: Determine Right Triangle 
7:40  
 
Extra Example 3: Determine Pythagorean Triple 
11:30  
 
Extra Example 4: Vertices and Right Triangle 
14:29  

Geometric Mean 
40:59 
 
Intro 
0:00  
 
Geometric Mean 
0:04  
 
 Geometric Mean & Example 
0:05  
 
Similar Triangles 
4:32  
 
 Similar Triangles 
4:33  
 
Geometric MeanAltitude 
11:10  
 
 Geometric MeanAltitude & Example 
11:11  
 
Geometric MeanLeg 
14:47  
 
 Geometric MeanLeg & Example 
14:18  
 
Extra Example 1: Geometric Mean Between Each Pair of Numbers 
20:10  
 
Extra Example 2: Similar Triangles 
23:46  
 
Extra Example 3: Geometric Mean of Triangles 
28:30  
 
Extra Example 4: Geometric Mean of Triangles 
36:58  

Special Right Triangles 
37:57 
 
Intro 
0:00  
 
454590 Triangles 
0:06  
 
 Definition of 454590 Triangles 
0:25  
 
454590 Triangles 
5:51  
 
 Example: Find n 
5:52  
 
306090 Triangles 
8:59  
 
 Definition of 306090 Triangles 
9:00  
 
306090 Triangles 
12:25  
 
 Example: Find n 
12:26  
 
Extra Example 1: Special Right Triangles 
15:08  
 
Extra Example 2: Special Right Triangles 
18:22  
 
Extra Example 3: Word Problems & Special Triangles 
27:40  
 
Extra Example 4: Hexagon & Special Triangles 
33:51  

Ratios in Right Triangles 
40:37 
 
Intro 
0:00  
 
Trigonometric Ratios 
0:08  
 
 Definition of Trigonometry 
0:13  
 
 Sine (sin), Cosine (cos), & Tangent (tan) 
0:50  
 
Trigonometric Ratios 
3:04  
 
 Trig Functions 
3:05  
 
 Inverse Trig Functions 
5:02  
 
SOHCAHTOA 
8:16  
 
 sin x 
9:07  
 
 cos x 
10:00  
 
 tan x 
10:32  
 
 Example: SOHCAHTOA & Triangle 
12:10  
 
Extra Example 1: Find the Value of Each Ratio or Angle Measure 
14:36  
 
Extra Example 2: Find Sin, Cos, and Tan 
18:51  
 
Extra Example 3: Find the Value of x Using SOHCAHTOA 
22:55  
 
Extra Example 4: Trigonometric Ratios in Right Triangles 
32:13  

Angles of Elevation and Depression 
21:04 
 
Intro 
0:00  
 
Angle of Elevation 
0:10  
 
 Definition of Angle of Elevation & Example 
0:11  
 
Angle of Depression 
1:19  
 
 Definition of Angle of Depression & Example 
1:20  
 
Extra Example 1: Name the Angle of Elevation and Depression 
2:22  
 
Extra Example 2: Word Problem & Angle of Depression 
4:41  
 
Extra Example 3: Word Problem & Angle of Elevation 
14:02  
 
Extra Example 4: Find the Missing Measure 
18:10  

Law of Sines 
35:25 
 
Intro 
0:00  
 
Law of Sines 
0:20  
 
 Law of Sines 
0:21  
 
Law of Sines 
3:34  
 
 Example: Find b 
3:35  
 
Solving the Triangle 
9:19  
 
 Example: Using the Law of Sines to Solve Triangle 
9:20  
 
Extra Example 1: Law of Sines and Triangle 
17:43  
 
Extra Example 2: Law of Sines and Triangle 
20:06  
 
Extra Example 3: Law of Sines and Triangle 
23:54  
 
Extra Example 4: Law of Sines and Triangle 
28:59  

Law of Cosines 
52:43 
 
Intro 
0:00  
 
Law of Cosines 
0:35  
 
 Law of Cosines 
0:36  
 
Law of Cosines 
6:22  
 
 Use the Law of Cosines When Both are True 
6:23  
 
Law of Cosines 
8:35  
 
 Example: Law of Cosines 
8:36  
 
Extra Example 1: Law of Sines or Law of Cosines? 
13:35  
 
Extra Example 2: Use the Law of Cosines to Find the Missing Measure 
17:02  
 
Extra Example 3: Solve the Triangle 
30:49  
 
Extra Example 4: Find the Measure of Each Diagonal of the Parallelogram 
41:39  
Section 9: Circles 

Segments in a Circle 
22:43 
 
Intro 
0:00  
 
Segments in a Circle 
0:10  
 
 Circle 
0:11  
 
 Chord 
0:59  
 
 Diameter 
1:32  
 
 Radius 
2:07  
 
 Secant 
2:17  
 
 Tangent 
3:10  
 
Circumference 
3:56  
 
 Introduction to Circumference 
3:57  
 
 Example: Find the Circumference of the Circle 
5:09  
 
Circumference 
6:40  
 
 Example: Find the Circumference of the Circle 
6:41  
 
Extra Example 1: Use the Circle to Answer the Following 
9:10  
 
Extra Example 2: Find the Missing Measure 
12:53  
 
Extra Example 3: Given the Circumference, Find the Perimeter of the Triangle 
15:51  
 
Extra Example 4: Find the Circumference of Each Circle 
19:24  

Angles and Arc 
35:24 
 
Intro 
0:00  
 
Central Angle 
0:06  
 
 Definition of Central Angle 
0:07  
 
Sum of Central Angles 
1:17  
 
 Sum of Central Angles 
1:18  
 
Arcs 
2:27  
 
 Minor Arc 
2:30  
 
 Major Arc 
3:47  
 
Arc Measure 
5:24  
 
 Measure of Minor Arc 
5:24  
 
 Measure of Major Arc 
6:53  
 
 Measure of a Semicircle 
7:11  
 
Arc Addition Postulate 
8:25  
 
 Arc Addition Postulate 
8:26  
 
Arc Length 
9:43  
 
 Arc Length and Example 
9:44  
 
Concentric Circles 
16:05  
 
 Concentric Circles 
16:06  
 
Congruent Circles and Arcs 
17:50  
 
 Congruent Circles 
17:51  
 
 Congruent Arcs 
18:47  
 
Extra Example 1: Minor Arc, Major Arc, and Semicircle 
20:14  
 
Extra Example 2: Measure and Length of Arc 
22:52  
 
Extra Example 3: Congruent Arcs 
25:48  
 
Extra Example 4: Angles and Arcs 
30:33  

Arcs and Chords 
21:51 
 
Intro 
0:00  
 
Arcs and Chords 
0:07  
 
 Arc of the Chord 
0:08  
 
 Theorem 1: Congruent Minor Arcs 
1:01  
 
Inscribed Polygon 
2:10  
 
 Inscribed Polygon 
2:11  
 
Arcs and Chords 
3:18  
 
 Theorem 2: When a Diameter is Perpendicular to a Chord 
3:19  
 
Arcs and Chords 
5:05  
 
 Theorem 3: Congruent Chords 
5:06  
 
Extra Example 1: Congruent Arcs 
10:35  
 
Extra Example 2: Length of Arc 
13:50  
 
Extra Example 3: Arcs and Chords 
17:09  
 
Extra Example 4: Arcs and Chords 
19:45  

Inscribed Angles 
27:53 
 
Intro 
0:00  
 
Inscribed Angles 
0:07  
 
 Definition of Inscribed Angles 
0:08  
 
Inscribed Angles 
0:58  
 
 Inscribed Angle Theorem 1 
0:59  
 
Inscribed Angles 
3:29  
 
 Inscribed Angle Theorem 2 
3:30  
 
Inscribed Angles 
4:38  
 
 Inscribed Angle Theorem 3 
4:39  
 
Inscribed Quadrilateral 
5:50  
 
 Inscribed Quadrilateral 
5:51  
 
Extra Example 1: Central Angle, Inscribed Angle, and Intercepted Arc 
7:02  
 
Extra Example 2: Inscribed Angles 
9:24  
 
Extra Example 3: Inscribed Angles 
14:00  
 
Extra Example 4: Complete the Proof 
17:58  

Tangents 
26:16 
 
Intro 
0:00  
 
Tangent Theorems 
0:04  
 
 Tangent Theorem 1 
0:05  
 
 Tangent Theorem 1 Converse 
0:55  
 
Common Tangents 
1:34  
 
 Common External Tangent 
2:12  
 
 Common Internal Tangent 
2:30  
 
Tangent Segments 
3:08  
 
 Tangent Segments 
3:09  
 
Circumscribed Polygons 
4:11  
 
 Circumscribed Polygons 
4:12  
 
Extra Example 1: Tangents & Circumscribed Polygons 
5:50  
 
Extra Example 2: Tangents & Circumscribed Polygons 
8:35  
 
Extra Example 3: Tangents & Circumscribed Polygons 
11:50  
 
Extra Example 4: Tangents & Circumscribed Polygons 
15:43  

Secants, Tangents, & Angle Measures 
27:50 
 
Intro 
0:00  
 
Secant 
0:08  
 
 Secant 
0:09  
 
Secant and Tangent 
0:49  
 
 Secant and Tangent 
0:50  
 
Interior Angles 
2:56  
 
 Secants & Interior Angles 
2:57  
 
Exterior Angles 
7:21  
 
 Secants & Exterior Angles 
7:22  
 
Extra Example 1: Secants, Tangents, & Angle Measures 
10:53  
 
Extra Example 2: Secants, Tangents, & Angle Measures 
13:31  
 
Extra Example 3: Secants, Tangents, & Angle Measures 
19:54  
 
Extra Example 4: Secants, Tangents, & Angle Measures 
22:29  

Special Segments in a Circle 
23:08 
 
Intro 
0:00  
 
Chord Segments 
0:05  
 
 Chord Segments 
0:06  
 
Secant Segments 
1:36  
 
 Secant Segments 
1:37  
 
Tangent and Secant Segments 
4:10  
 
 Tangent and Secant Segments 
4:11  
 
Extra Example 1: Special Segments in a Circle 
5:53  
 
Extra Example 2: Special Segments in a Circle 
7:58  
 
Extra Example 3: Special Segments in a Circle 
11:24  
 
Extra Example 4: Special Segments in a Circle 
18:09  

Equations of Circles 
27:01 
 
Intro 
0:00  
 
Equation of a Circle 
0:06  
 
 Standard Equation of a Circle 
0:07  
 
 Example 1: Equation of a Circle 
0:57  
 
 Example 2: Equation of a Circle 
1:36  
 
Extra Example 1: Determine the Coordinates of the Center and the Radius 
4:56  
 
Extra Example 2: Write an Equation Based on the Given Information 
7:53  
 
Extra Example 3: Graph Each Circle 
16:48  
 
Extra Example 4: Write the Equation of Each Circle 
19:17  
Section 10: Polygons & Area 

Polygons 
27:24 
 
Intro 
0:00  
 
Polygons 
0:10  
 
 Polygon vs. Not Polygon 
0:18  
 
Convex and Concave 
1:46  
 
 Convex vs. Concave Polygon 
1:52  
 
Regular Polygon 
4:04  
 
 Regular Polygon 
4:05  
 
Interior Angle Sum Theorem 
4:53  
 
 Triangle 
5:03  
 
 Quadrilateral 
6:05  
 
 Pentagon 
6:38  
 
 Hexagon 
7:59  
 
 20Gon 
9:36  
 
Exterior Angle Sum Theorem 
12:04  
 
 Exterior Angle Sum Theorem 
12:05  
 
Extra Example 1: Drawing Polygons 
13:51  
 
Extra Example 2: Convex Polygon 
15:16  
 
Extra Example 3: Exterior Angle Sum Theorem 
18:21  
 
Extra Example 4: Interior Angle Sum Theorem 
22:20  

Area of Parallelograms 
17:46 
 
Intro 
0:00  
 
Parallelograms 
0:06  
 
 Definition and Area Formula 
0:07  
 
Area of Figure 
2:00  
 
 Area of Figure 
2:01  
 
Extra Example 1:Find the Area of the Shaded Area 
3:14  
 
Extra Example 2: Find the Height and Area of the Parallelogram 
6:00  
 
Extra Example 3: Find the Area of the Parallelogram Given Coordinates and Vertices 
10:11  
 
Extra Example 4: Find the Area of the Figure 
14:31  

Area of Triangles Rhombi, & Trapezoids 
20:31 
 
Intro 
0:00  
 
Area of a Triangle 
0:06  
 
 Area of a Triangle: Formula and Example 
0:07  
 
Area of a Trapezoid 
2:31  
 
 Area of a Trapezoid: Formula 
2:32  
 
 Area of a Trapezoid: Example 
6:55  
 
Area of a Rhombus 
8:05  
 
 Area of a Rhombus: Formula and Example 
8:06  
 
Extra Example 1: Find the Area of the Polygon 
9:51  
 
Extra Example 2: Find the Area of the Figure 
11:19  
 
Extra Example 3: Find the Area of the Figure 
14:16  
 
Extra Example 4: Find the Height of the Trapezoid 
18:10  

Area of Regular Polygons & Circles 
36:43 
 
Intro 
0:00  
 
Regular Polygon 
0:08  
 
 SOHCAHTOA 
0:54  
 
 306090 Triangle 
1:52  
 
 454590 Triangle 
2:40  
 
Area of a Regular Polygon 
3:39  
 
 Area of a Regular Polygon 
3:40  
 
Are of a Circle 
7:55  
 
 Are of a Circle 
7:56  
 
Extra Example 1: Find the Area of the Regular Polygon 
8:22  
 
Extra Example 2: Find the Area of the Regular Polygon 
16:48  
 
Extra Example 3: Find the Area of the Shaded Region 
24:11  
 
Extra Example 4: Find the Area of the Shaded Region 
32:24  

Perimeter & Area of Similar Figures 
18:17 
 
Intro 
0:00  
 
Perimeter of Similar Figures 
0:08  
 
 Example: Scale Factor & Perimeter of Similar Figures 
0:09  
 
Area of Similar Figures 
2:44  
 
 Example:Scale Factor & Area of Similar Figures 
2:55  
 
Extra Example 1: Complete the Table 
6:09  
 
Extra Example 2: Find the Ratios of the Perimeter and Area of the Similar Figures 
8:56  
 
Extra Example 3: Find the Unknown Area 
12:04  
 
Extra Example 4: Use the Given Area to Find AB 
14:26  

Geometric Probability 
38:40 
 
Intro 
0:00  
 
Length Probability Postulate 
0:05  
 
 Length Probability Postulate 
0:06  
 
Are Probability Postulate 
2:34  
 
 Are Probability Postulate 
2:35  
 
Are of a Sector of a Circle 
4:11  
 
 Are of a Sector of a Circle Formula 
4:12  
 
 Are of a Sector of a Circle Example 
7:51  
 
Extra Example 1: Length Probability 
11:07  
 
Extra Example 2: Area Probability 
12:14  
 
Extra Example 3: Area Probability 
17:17  
 
Extra Example 4: Area of a Sector of a Circle 
26:23  
Section 11: Solids 

ThreeDimensional Figures 
23:39 
 
Intro 
0:00  
 
Polyhedrons 
0:05  
 
 Polyhedrons: Definition and Examples 
0:06  
 
 Faces 
1:08  
 
 Edges 
1:55  
 
 Vertices 
2:23  
 
Solids 
2:51  
 
 Pyramid 
2:54  
 
 Cylinder 
3:45  
 
 Cone 
4:09  
 
 Sphere 
4:23  
 
Prisms 
5:00  
 
 Rectangular, Regular, and Cube Prisms 
5:02  
 
Platonic Solids 
9:48  
 
 Five Types of Regular Polyhedra 
9:49  
 
Slices and Cross Sections 
12:07  
 
 Slices 
12:08  
 
 Cross Sections 
12:47  
 
Extra Example 1: Name the Edges, Faces, and Vertices of the Polyhedron 
14:23  
 
Extra Example 2: Determine if the Figure is a Polyhedron and Explain Why 
17:37  
 
Extra Example 3: Describe the Slice Resulting from the Cut 
19:12  
 
Extra Example 4: Describe the Shape of the Intersection 
21:25  

Surface Area of Prisms and Cylinders 
38:50 
 
Intro 
0:00  
 
Prisms 
0:06  
 
 Bases 
0:07  
 
 Lateral Faces 
0:52  
 
 Lateral Edges 
1:19  
 
 Altitude 
1:58  
 
Prisms 
2:24  
 
 Right Prism 
2:25  
 
 Oblique Prism 
2:56  
 
Classifying Prisms 
3:27  
 
 Right Rectangular Prism 
3:28  
 
 
4:55  
 
 Oblique Pentagonal Prism 
6:26  
 
 Right Hexagonal Prism 
7:14  
 
Lateral Area of a Prism 
7:42  
 
 Lateral Area of a Prism 
7:43  
 
Surface Area of a Prism 
13:44  
 
 Surface Area of a Prism 
13:45  
 
Cylinder 
16:18  
 
 Cylinder: Right and Oblique 
16:19  
 
Lateral Area of a Cylinder 
18:02  
 
 Lateral Area of a Cylinder 
18:03  
 
Surface Area of a Cylinder 
20:54  
 
 Surface Area of a Cylinder 
20:55  
 
Extra Example 1: Find the Lateral Area and Surface Are of the Prism 
21:51  
 
Extra Example 2: Find the Lateral Area of the Prism 
28:15  
 
Extra Example 3: Find the Surface Area of the Prism 
31:57  
 
Extra Example 4: Find the Lateral Area and Surface Area of the Cylinder 
34:17  

Surface Area of Pyramids and Cones 
26:10 
 
Intro 
0:00  
 
Pyramids 
0:07  
 
 Pyramids 
0:08  
 
Regular Pyramids 
1:52  
 
 Regular Pyramids 
1:53  
 
Lateral Area of a Pyramid 
4:33  
 
 Lateral Area of a Pyramid 
4:34  
 
Surface Area of a Pyramid 
9:19  
 
 Surface Area of a Pyramid 
9:20  
 
Cone 
10:09  
 
 Right and Oblique Cone 
10:10  
 
Lateral Area and Surface Area of a Right Cone 
11:20  
 
 Lateral Area and Surface Are of a Right Cone 
11:21  
 
Extra Example 1: Pyramid and Prism 
13:11  
 
Extra Example 2: Find the Lateral Area of the Regular Pyramid 
15:00  
 
Extra Example 3: Find the Surface Area of the Pyramid 
18:29  
 
Extra Example 4: Find the Lateral Area and Surface Area of the Cone 
22:08  

Volume of Prisms and Cylinders 
21:59 
 
Intro 
0:00  
 
Volume of Prism 
0:08  
 
 Volume of Prism 
0:10  
 
Volume of Cylinder 
3:38  
 
 Volume of Cylinder 
3:39  
 
Extra Example 1: Find the Volume of the Prism 
5:10  
 
Extra Example 2: Find the Volume of the Cylinder 
8:03  
 
Extra Example 3: Find the Volume of the Prism 
9:35  
 
Extra Example 4: Find the Volume of the Solid 
19:06  

Volume of Pyramids and Cones 
22:02 
 
Intro 
0:00  
 
Volume of a Cone 
0:08  
 
 Volume of a Cone: Example 
0:10  
 
Volume of a Pyramid 
3:02  
 
 Volume of a Pyramid: Example 
3:03  
 
Extra Example 1: Find the Volume of the Pyramid 
4:56  
 
Extra Example 2: Find the Volume of the Solid 
6:01  
 
Extra Example 3: Find the Volume of the Pyramid 
10:28  
 
Extra Example 4: Find the Volume of the Octahedron 
16:23  

Surface Area and Volume of Spheres 
14:46 
 
Intro 
0:00  
 
Special Segments 
0:06  
 
 Radius 
0:07  
 
 Chord 
0:31  
 
 Diameter 
0:55  
 
 Tangent 
1:20  
 
Sphere 
1:43  
 
 Plane & Sphere 
1:44  
 
 Hemisphere 
2:56  
 
Surface Area of a Sphere 
3:25  
 
 Surface Area of a Sphere 
3:26  
 
Volume of a Sphere 
4:08  
 
 Volume of a Sphere 
4:09  
 
Extra Example 1: Determine Whether Each Statement is True or False 
4:24  
 
Extra Example 2: Find the Surface Area of the Sphere 
6:17  
 
Extra Example 3: Find the Volume of the Sphere with a Diameter of 20 Meters 
7:25  
 
Extra Example 4: Find the Surface Area and Volume of the Solid 
9:17  

Congruent and Similar Solids 
16:06 
 
Intro 
0:00  
 
Scale Factor 
0:06  
 
 Scale Factor: Definition and Example 
0:08  
 
Congruent Solids 
1:09  
 
 Congruent Solids 
1:10  
 
Similar Solids 
2:17  
 
 Similar Solids 
2:18  
 
Extra Example 1: Determine if Each Pair of Solids is Similar, Congruent, or Neither 
3:35  
 
Extra Example 2: Determine if Each Statement is True or False 
7:47  
 
Extra Example 3: Find the Scale Factor and the Ratio of the Surface Areas and Volume 
10:14  
 
Extra Example 4: Find the Volume of the Larger Prism 
12:14  
Section 12: Transformational Geometry 

Mapping 
14:12 
 
Intro 
0:00  
 
Transformation 
0:04  
 
 Rotation 
0:32  
 
 Translation 
1:03  
 
 Reflection 
1:17  
 
 Dilation 
1:24  
 
Transformations 
1:45  
 
 Examples 
1:46  
 
Congruence Transformation 
2:51  
 
 Congruence Transformation 
2:52  
 
Extra Example 1: Describe the Transformation that Occurred in the Mappings 
3:37  
 
Extra Example 2: Determine if the Transformation is an Isometry 
5:16  
 
Extra Example 3: Isometry 
8:16  

Reflections 
23:17 
 
Intro 
0:00  
 
Reflection 
0:05  
 
 Definition of Reflection 
0:06  
 
 Line of Reflection 
0:35  
 
 Point of Reflection 
1:22  
 
Symmetry 
1:59  
 
 Line of Symmetry 
2:00  
 
 Point of Symmetry 
2:48  
 
Extra Example 1: Draw the Image over the Line of Reflection and the Point of Reflection 
3:45  
 
Extra Example 2: Determine Lines and Point of Symmetry 
6:59  
 
Extra Example 3: Graph the Reflection of the Polygon 
11:15  
 
Extra Example 4: Graph the Coordinates 
16:07  

Translations 
18:43 
 
Intro 
0:00  
 
Translation 
0:05  
 
 Translation: Preimage & Image 
0:06  
 
 Example 
0:56  
 
Composite of Reflections 
6:28  
 
 Composite of Reflections 
6:29  
 
Extra Example 1: Translation 
7:48  
 
Extra Example 2: Image, Preimage, and Translation 
12:38  
 
Extra Example 3: Find the Translation Image Using a Composite of Reflections 
15:08  
 
Extra Example 4: Find the Value of Each Variable in the Translation 
17:18  

Rotations 
21:26 
 
Intro 
0:00  
 
Rotations 
0:04  
 
 Rotations 
0:05  
 
Performing Rotations 
2:13  
 
 Composite of Two Successive Reflections over Two Intersecting Lines 
2:14  
 
 Angle of Rotation: Angle Formed by Intersecting Lines 
4:29  
 
Angle of Rotation 
5:30  
 
 Rotation Postulate 
5:31  
 
Extra Example 1: Find the Rotated Image 
7:32  
 
Extra Example 2: Rotations and Coordinate Plane 
10:33  
 
Extra Example 3: Find the Value of Each Variable in the Rotation 
14:29  
 
Extra Example 4: Draw the Polygon Rotated 90 Degree Clockwise about P 
16:13  

Dilation 
37:06 
 
Intro 
0:00  
 
Dilations 
0:06  
 
 Dilations 
0:07  
 
Scale Factor 
1:36  
 
 Scale Factor 
1:37  
 
 Example 1 
2:06  
 
 Example 2 
6:22  
 
Scale Factor 
8:20  
 
 Positive Scale Factor 
8:21  
 
 Negative Scale Factor 
9:25  
 
 Enlargement 
12:43  
 
 Reduction 
13:52  
 
Extra Example 1: Find the Scale Factor 
16:39  
 
Extra Example 2: Find the Measure of the Dilation Image 
19:32  
 
Extra Example 3: Find the Coordinates of the Image with Scale Factor and the Origin as the Center of Dilation 
26:18  
 
Extra Example 4: Graphing Polygon, Dilation, and Scale Factor 
32:08  