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Proving Triangles Congruent

  • SSS (Side-Side-Side) Postulate: If the sides of one triangle are congruent to the sides of a second triangle, then the triangles are congruent
  • SAS (Side-Angle-Side) Postulate: If two sides and the included angle of one triangle are congruent to two sides and the included angle of another triangle, then the triangles are congruent
  • ASA (Angle-Side-Angle) Postulate: If two angles and the included side of one triangle are congruent to two angles and the included side of another triangle, then the triangles are congruent
  • AAS (Angle-Angle-Side) Theorem: If two angles and a non-included side of one triangle are congruent to the corresponding two angles and side of a second triangle, then the two triangles are congruent.
  • CPCTC (Corresponding Parts of Congruent Triangles are Congruent)

Proving Triangles Congruent

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.

Mathematics: Geometry