A right triangle has one angle that measures exactly 90°. This type of triangle has special properties studied by the mathematician Pythagoras.
The Pythagorean theorem states: "the square of the hypotenuse equals the sum of the squares of the two legs".
The legs are the two sides of the right triangle that form the 90° angle.
It is the side of the right triangle that does not form the 90° angle. It is always the longest side.
The Pythagorean Theorem Formula
When you know both legs, you can find the hypotenuse with:
The same relationship written another way:
Both expressions are equivalent and give the same result.
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