Pythagoras’ theorem was found on a Babylonian tablet created 1200 years before Pythagoras himself

On the ancient Babylonian tablet IM 67118, dated 1770 BC, was found Pythagoras’ theorem, which was used to determine the length of the diagonal inside a rectangle. This occurred several centuries before Pythagoras was born: he was born around 570 BC.

Another tablet, dated around 1800-1600 BC, revealed a square with signed triangles inside, indicating that the ancient Babylonians were aware of Pythagoras’ theorem and other mathematical concepts.