Triangle Exterior Angles and Equations
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Objective
I can write and solve equations to find missing angle measures in triangles using the exterior angle theorem.
Part 1 of 3
Warm-up video
Unknown Channel · 5:00
We don't generate video — this one is by Unknown Channel 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 3
Practice
7 questions
Explain in your own words how to find a missing angle in a triangle when you know the other two angles.
In triangle XYZ, ∠X = 65° and ∠Y = 45°. Draw a diagram of the triangle and calculate the measure of ∠Z. [Diagram of triangle XYZ with ∠X = 65° and ∠Y = 45°]
Part 3 of 3
Exit ticket
Quick comprehension check
“In a triangle, two interior angles measure 40° and 65°. Find the measure of the exterior angle formed at the vertex of the third interior angle. An exterior angle of a triangle measures 130°. One of the non-adjacent interior angles measures 50°. Find the measure of the other non-adjacent interior angle. ”
Sample answer included in the free materials
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