## Reflection: Student Ownership CPCTC and Isosceles Triangles - Section 3: Discussion: Corresponding Parts of Congruent Triangles

It has been my experience over the years that students love to use CPCTC as a reason in proofs, regardless of the statement to which they are attaching it. I therefore spend a good deal of time throughout this unit asking Corresponding parts of what?? Over and over again, I ask students to explain to me and to their classmates what is required when using CPCTC, emphasizing that they must first have congruent triangles, in order to use this as a reason in their proofs.

Avoiding Random Use of CPCTC
Student Ownership: Avoiding Random Use of CPCTC

# CPCTC and Isosceles Triangles

Unit 5: Polygons and Congruent Triangle Proofs
Lesson 2 of 6

## Big Idea: Students continue to explore congruent triangles, focusing on corresponding parts and angle and side relationships in isosceles triangles.

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90 minutes

### Beth Menzie

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