Calculating Angles with Trig Functions
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Objective
I can calculate the measure of an angle in a right triangle using sine, cosine, or tangent.
Part 1 of 4
Warm-up video
Khan Academy · 9:17Vetted channel
We don't generate video — this one is by Khan Academy 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
Trigonometry is the study of the ratios of sides of triangles.
- 2
The mnemonic SOH CAH TOA is helpful for remembering that Sine = Opposite/Hypotenuse, Cosine = Adjacent/Hypotenuse, and Tangent = Opposite/Adjacent.
- 3
The hypotenuse is the side opposite the right angle in a right triangle and is always the longest side.
Part 3 of 4
Practice
8 questions
What does the term 'trig' in trigonometry refer to?
In a right triangle, which side is opposite the right angle?
Part 4 of 4
Exit ticket
Quick comprehension check
“In a right triangle, the side opposite angle θ is 8 cm and the adjacent side is 15 cm. What is the measure of angle θ in degrees?”
Sample answer included in the free materials
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