45-45-90 Triangles Page 1 of 5
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What is a 45-45-90 Triangle?
What do you know about a square? All 4 sides are the same length. Since a 45-45-90 triangle is half of a square, this means that the two sides that form the 90 degree angle are the same length.
For this reason, a 45-45-90 triangle is often referred to as an isosceles right triangle. If you know one of the legs of a 45-45-90 triangle, the other leg will be the same.
We know that one leg of this 45-45-90 triangle is 7 units long. The two legs that form the right angle in a 45-45-90 triangle are always the same length.
This means that x is also 7.
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