45-45-90 and 30-60-90 Triangles
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Objective
I can calculate the side lengths of 45-45-90 and 30-60-90 triangles.
Part 1 of 4
Warm-up video
Khan Academy · 5:42Vetted 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
A 45-45-90 triangle is also known as a right isosceles triangle because it has a right angle and two equal sides.
- 2
In a 45-45-90 triangle, if both legs are length x, the hypotenuse is equal to x√2.
- 3
The ratio of the sides in a 45-45-90 triangle is 1 to 1 to √2.
Part 3 of 4
Practice
10 questions
In a 30-60-90 triangle, the side opposite the 30-degree angle is 5. What is the length of the hypotenuse?
A 45-45-90 triangle has a leg length of 7. What is the length of the other leg?
Part 4 of 4
Exit ticket
Quick comprehension check
“In a 45-45-90 triangle, one of the legs has a length of 7. What are the lengths of the other leg and the hypotenuse?”
Sample answer included in the free materials
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