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2.A: Proving Triangle Congruence

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Overview

The purpose of this lesson is to identify when we can claim two triangles are congruent.

This lesson will address the following CCRS Standard(s) for Geometry:

• 8.G.2: Understand that a two-dimensional figure is congruent to another if the second can be obtained from the first by a sequence of rotations, reflections, and translations; given two congruent figures, describe a sequence that exhibits the congruence between them
• G.SRT.5: Use congruence and similarity criteria for triangles to solve problems and to prove relationships in geometric figures

Directions

1. Take notes while watching videos below
2. Go to http://wamap.org and log into our course to complete assignment 2.A with 80% or better.

Do

Complete assignment 2.A with 80% or better at http://wamap.org

Summary

In this lesson we have learned:

• To identify congruent triangles we need to know three parts are congruent: SSS, SAS, ASA, or AAS
• The following combinations do not necessarily indicate congruence: ASS and AAA