Finding Missing Sides with Pythagoras
Learning Objective
I can use the Pythagorean theorem to find missing side lengths of right triangles, relating them to the angles.
Key Concepts
In a 45-45-90 triangle, the two sides opposite the 45 degree angles are congruent, and the hypotenuse is equal to the side length times the square root of 2.
In a 30-60-90 triangle, the shortest side is opposite the 30 degree angle, and the hypotenuse is twice the length of the shortest side.
In a 30-60-90 triangle, the longer leg is equal to the short side times the square root of 3.
Practice Questions
This lesson includes 12 practice questions to reinforce learning.
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1. In a 45-45-90 triangle, if one side length is 7, what is the length of the other side?
2. What is the ratio of the sides in a 45-45-90 triangle?
3. If the hypotenuse of a 45-45-90 triangle is 9√2, what is the length of each side?
...and 9 more questions
Educational Video
How Special Right Triangles Work | 45-45-90 and 30-60-90
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