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Using Congruent Triangles

Related Topics:
Common Core (Geometry)
Common Core for Mathematics



Examples, solutions, 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

CPCTC is an acronym for Corresponding Parts of Congruent Triangles are Congruent. It means that once two triangles are proven to be congruent, then the three pairs of sides that correspond must be congruent and the three pairs of angles that correspond must be congruent.

CPCTC is usually used at the end of a proof to show that two angles or two sides are congruent.

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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