Right Triangles and the Pythagorean Theorem
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Objective
I can use the Pythagorean theorem to find the missing side length of a right triangle.
Part 1 of 4
Warm-up video
Kayla Jones · 5:20
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
The acronym SOH CAH TOA is a helpful way to remember the trigonometric ratios: Sine = Opposite/Hypotenuse, Cosine = Adjacent/Hypotenuse, Tangent = Opposite/Adjacent.
- 2
To find a missing side of a right triangle using trigonometry, first identify the angle and the two sides you are given, then choose the appropriate trigonometric function.
- 3
If the variable is in the denominator, you must multiply both sides by the variable before isolating it; if the variable is in the numerator, you must multiply both sides by the denominator to isolate the variable.
Part 3 of 4
Practice
10 questions
What is the first step in finding a missing side of a right triangle using trigonometric functions?
In a right triangle, if you know the angle and the length of the opposite side, and you want to find the hypotenuse, which trigonometric function should you use?
Part 4 of 4
Exit ticket
Quick comprehension check
“In a right triangle, the angle is 61°. The opposite side is 23. Find the length of the hypotenuse. Show your work.”
Sample answer included in the free materials
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