30-60-90 Triangle Ratios
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Objective
I can determine the side lengths of a 30-60-90 triangle using the ratio relationships.
Part 1 of 4
Warm-up video
Khan Academy · 4:49Vetted 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
In a 30-60-90 triangle, the side opposite the 30-degree angle is always half the length of the hypotenuse.
- 2
In a 30-60-90 triangle, the side opposite the 60-degree angle is equal to √3/2 times the length of the hypotenuse.
- 3
To rationalize a denominator that includes a square root, multiply both the numerator and the denominator by the square root in the denominator.
Part 3 of 4
Practice
10 questions
In a 30-60-90 triangle, the side opposite the 30-degree angle is always what fraction of the hypotenuse?
In a 30-60-90 triangle, if the hypotenuse has a length of 8, what is the length of the side opposite the 30-degree angle?
Part 4 of 4
Exit ticket
Quick comprehension check
“A 30-60-90 triangle has a hypotenuse of length 8. What be the lengths of the other two sides? Show your work.”
Sample answer included in the free materials
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