Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Co, G Srt Congruence of Parallelograms

For Teachers 9th - 10th Standards
In this task, a student has learned the SSS and SAS congruence tests for triangles and wonders if these tests might work for parallelograms. Aligns with G-CO.C.11 and G-SRT.B.5
Website
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Congruence and Triangles

For Students 9th - 10th Standards
This site gives a very thorough explanation of how to tell if two triangles are congruent. Dr. Math explains why SSS, SAS, ASA determine that two triangles are congruent. The Dr. gives a few exercises for the reader to try then gives the...
Handout
Jim Loy

Jim Loy's Mathematics Page: Congruence of Triangles

For Students 9th - 10th Standards
Find explanations of the ways to prove triangles are congruent. There is a link for Congruence Of Triangles, Part II to find the proofs of some ways to prove congruence of triangles from other postulates (i.e. Assume SAS prove ASA).
Whiteboard
ClassFlow

Class Flow: Congruence in Triangles

For Teachers 9th - 10th Standards
[Free Registration/Login Required] This lesson helps teach congrence in triangles. Includes practice with postulates, theorems, and logical reasoning.