Labeling Right Triangle Sides
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Objective
I can label the sides of a right triangle as opposite, adjacent, and hypotenuse, relative to a given angle.
Part 1 of 4
Warm-up video
Kayla Jones · 6:59
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
In a right triangle, the hypotenuse is always across from the right angle, and the other sides are named relative to a specific angle, θ (theta).
- 2
The side across from angle θ is called the opposite side, while the side next to θ is the adjacent side.
- 3
SOH CAH TOA is an acronym that defines the trigonometric ratios: Sine = Opposite/Hypotenuse, Cosine = Adjacent/Hypotenuse, Tangent = Opposite/Adjacent.
Part 3 of 4
Practice
9 questions
In a right triangle, which side is always opposite the right angle?
What does 'theta' typically represent in trigonometry?
Part 4 of 4
Exit ticket
Quick comprehension check
“In a right triangle, angle θ is one of the acute angles. Side AC is across from angle θ, and side BC is next to angle θ. Side AB is across from the right angle. Label each side (AC, BC, and AB) as either opposite, adjacent, or hypotenuse relative to angle θ.”
Sample answer included in the free materials
Get the materials
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Teacher Guide
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