Weegy: The Pythagorean Theorem is a mathematical formula that relates to the three sides of a right triangle. It states that in a right triangle, the square of the length of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the lengths of the other two sides. The theorem can be written algebraically as: a^2 + b^2 = c^2 where "a" and "b" are the lengths of the two legs of the right triangle, and "c" is the length of the hypotenuse. This theorem is named after the ancient Greek mathematician Pythagoras, who is credited with its discovery and proof. [ ] (More)