What does the Angle Addition Postulate state?

If point X is interior to ∠ABC, then m∠ABX + m∠XBC = m∠ABC.

Solving for Angles with Addition

Name: Solving for Angles with Addition
Author: Insta~Lesson

10th Grade · Math · 50 min

I can use the angle addition postulate to solve for unknown angle measures.

1
The Angle Addition Postulate states if point X is interior to ∠ABC, then m∠ABX + m∠XBC = m∠ABC.
2
If m∠KLB = 26° and m∠BLM = 60°, and B is interior to ∠KLM, then m∠KLM = 86°.
3
If m∠EDC = 145° and m∠EDW = 61°, then to find m∠WDC, we can subtract 61° from 145°.

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