## Notes: Triangle Sum, Isosceles Triangles - Section 3: Debrief Notes

Notes: Triangle Sum, Isosceles Triangles

# Triangle Sum Theorem and Special Triangles

Unit 7: Discovering and Proving Triangle Properties
Lesson 2 of 10

## Big Idea: By investigating the angles of four different types of triangles, students conjecture about the interior angle sum of triangles and ultimately prove the triangle sum theorem.

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6 teachers like this lesson
Standards:
Subject(s):
Math, Geometry, Triangles, reasoning and proof, Triangle Sum Theorem, Triangle Congruence, triangle similarity
85 minutes

### Jessica Uy

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