In China, Shang Gao of the Zhou Dynasty put forward a special case of Pythagorean Theorem "Hook three strands, four chords and five". In the west, the Pythagorean school of ancient Greece in the 6th century BC first proposed and proved this theorem. He proved by deduction that the square of the hypotenuse of a right triangle is equal to the sum of the squares of two right angles.

There are about 500 ways to prove Pythagorean theorem, and Pythagorean theorem is one of the most proven theorems in mathematics. Pythagorean theorem is one of the important mathematical theorems discovered and proved by human beings in the early days. It is one of the most important tools to solve geometric problems with algebraic ideas, and it is also one of the ties of the combination of numbers and shapes.