Parallel Lines and Perpendicular Lines
Parallel lines are two lines in the same plane that do not intersect. Two non-vertical lines are parallel if and only if they have the same slope.
If you are given the equation of a line and a point not on that line, you can find the equation of the line through this point parallel to the given line by using the point-slope form.
Perpendicular lines are lines that intersect at right angles. Two non-vertical lines are perpendicular if and only if the product of their slopes is 1 (or, equivalently, their slopes are negative reciprocals of each other).
You can use this fact to determine whether a pairs of lines whose equations have been given are perpendicular or not.
If you are given the equation of a line and a point, you can find the equation of the line through this point perpendicular to the given line by using the point-slope form. You must first find the slope of the given line and then take its negative reciprocal.
Parallel Lines and Perpendicular Lines
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.



























Carleen Eaton
Grant Fraser




Start Learning Now
Our free lessons will get you started (Flash® 10 required).
Sign up for Educator.comGet immediate access to our entire library.
Features Overview