## Angles of a Triangle Activity - Section 3: Activity

Angles of a Triangle Activity

# Angles of Triangles

Unit 7: Proofs about Triangles
Lesson 3 of 11

## Big Idea: Students will use paper triangles to perform informal proofs about the sum of the interior angles and exterior angles of triangles.

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1 teacher likes this lesson
Standards:
Subject(s):
Math, Geometry, Proofs, triangle, Triangle Proofs
45 minutes

### Marisa Laks

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