 # Using Congruent Triangles

Videos and lessons to help High School students learn how to use congruence and similarity criteria for triangles to solve problems and to prove relationships in geometric figures.

Common Core: HSG-SRT.B.5

Using CPCTC (Corresponding Parts of Congruent Triangles are Congruent)
Using triangle congruence and cpctc in overlapping triangles prove other properties.

Proofs using CPCTC

Use Congruent Triangles
Lesson Notes on Using Triangle Congruence, includes Corresponding Parts of Congruent Triangles are Congruent (CPCTC)
Explain how you can find the distance across the canyon.

Use Congruent Triangles
Use congruent triangles to find the distance between two docked boats.
Plan a proof involving pairs of triangles
Proof the construction for copying an obtuse angle is valid.

Use Congruent Triangles to find distance.

Use Congruent Triangles for indirect measurement.

Using Congruent Triangles.

Using Congruent Triangles.

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