The Pythagorean theorem is often used to find the missing side length(s) of a right triangle. A right triangle is a three sided shape with three interior angles, and all triangles inner angles add to equal 180°. In a right triangle, one of the angles measures 90°. This makes the other two angles acute, with a sum of 90°.
The equation is a^2 + b^2 = c^2.
If ‘a’ and ‘b’ represent the lengths of the legs of a right triangle and ‘c’ is the length of the hypotenuse, then the sum of the squared lengths is equal to the square of the length of the hypotenuse. The hypotenuse is the longest side of the triangle, and the one opposite (across from) the 90° angle.