Right Triangle Trigonometry
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Objective
I can use sine, cosine, and tangent to find the missing side length of a right triangle.
Part 1 of 3
Warm-up video
VividMath · 4:42
We don't generate video — this one is by VividMath 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 sine (sin) and cosine (cos) in terms of the sides of a right triangle (opposite, adjacent, hypotenuse).
In a right triangle, if sin(θ) = ⅖, what is the value of cos(90° - θ)? Explain your answer.
Part 3 of 3
Exit ticket
Quick comprehension check
“In a right triangle, angle θ is 30° and the hypotenuse is 10 cm. Find the length of the side opposite angle θ. In a right triangle, angle θ is 60° and the side adjacent to angle θ is 5 cm. Find the length of the hypotenuse. In a right triangle, angle θ is 45° and the side opposite angle θ is 7 cm. Find the length of the side adjacent to angle θ.”
Sample answer included in the free materials
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