Solving for Missing Angles
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Objective
I can solve for a missing angle or variable in complementary angle problems.
Part 1 of 4
Warm-up video
Kayla Jones · 2:45
We don't generate video — this one is by Kayla Jones 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
Complementary angles are two or more angles that add up to 90 degrees.
- 2
If one angle is 27° and the two angles are complementary, the other angle can be found by solving the equation 27 + B = 90, so B = 63°.
- 3
When solving for x in a complementary angle problem, set up an equation where the sum of the angles equals 90 degrees, then combine like terms and isolate x.
Part 3 of 4
Practice
11 questions
What is the definition of complementary angles?
If angle A is 35 degrees and angle B is its complement, what is the measure of angle B?
Part 4 of 4
Exit ticket
Quick comprehension check
“Two angles are complementary. One angle measures 3x + 2 degrees and the other measures 28 degrees. Solve for x.”
Sample answer included in the free materials
Get the materials
Teacher guide, student handout, and slides — free, in Google Docs format
Teacher Guide
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Student Handout
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