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Algebra basics (ASL)

Course: Algebra basics (ASL) > Unit 8

Lesson 2: Triangle angles (ASL)
Math
Algebra basics (ASL)
Equations and geometry (ASL)
Triangle angles (ASL)
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Angles in a triangle sum to 180° proof

Google Classroom
Learn the formal proof that shows the measures of interior angles of a triangle sum to 180°. Created by Sal Khan.

Video transcript