Isosceles Triangle Calculations
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Objective
I can calculate missing angles or side lengths in isosceles triangles.
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
Define an isosceles triangle in your own words, mentioning its key properties related to sides and angles.
In an isosceles triangle, one of the base angles measures 65°. What is the measure of the other base angle? Explain your reasoning.
Part 3 of 3
Exit ticket
Quick comprehension check
“In isosceles triangle DEF, DE = DF. If angle E measures 70°, find the measure of angle F. In isosceles triangle PQR, PQ = PR. If angle P measures 34°, find the measure of angle Q. ”
Sample answer included in the free materials
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