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Videos, worksheets, solutions, and activities to help Geometry students learn about CPCTC. CPCTC is an acronym for corresponding parts of congruent triangles are congruent.

CPCTC

CPCTC is an acronym for corresponding parts of congruent triangles are congruent. CPCTC is commonly used at or near the end of a proof which asks the student to show that two angles or two sides 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.

How do we use CPCTC to prove corresponding parts of triangles?

Learn to identify and apply the CPCTC rule

Anytime you are required to prove corresponding parts of congruent triangles congruent, you will be doing a triangle proof. The two examples in this post use AAS and SAS before proving the other part of the triangle congruent using CPCTC.

You can use the Mathway widget below to practice Algebra or other math topics. Try the given examples, or type in your own problem. Then click "Answer" to check your answer.