Solving for Angles with Addition
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Objective
I can use the angle addition postulate to solve for unknown angle measures.
Part 1 of 4
Warm-up video
MaeMap · 11:41
We don't generate video — this one is by MaeMap on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 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°.
Part 3 of 4
Practice
9 questions
What does the Angle Addition Postulate state?
If m∠PQR = 75° and point S is in the interior of ∠PQR such that m∠PQS = 40°, what is m∠SQR?
Part 4 of 4
Exit ticket
Quick comprehension check
“If m∠ABC = 120° and m∠ABD = 35°, find m∠DBC.”
Sample answer included in the free materials
Get the materials
Teacher guide, student handout, and slides — free, in Google Docs format
Teacher Guide
Complete lesson plan with answer keys and alternate activities
Student Handout
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