It is difficult to find a man whose name we do not associate it with the theorem of Pythagoras. Even those who in their lives far from mathematics, continue to preserve the memories of «the Pythagorean pants» - the square of the hypotenuse, the равновеликом two squares on катетах. The reason for such popularity of the theorem of Pythagoras is clear: it is the simplicity - beauty - importance. In fact, the Pythagorean theorem is simple, but not obvious. The contradiction of two elements and gives it its particular fascination, makes her beautiful. But, in addition, the Pythagorean theorem is of great importance. It is used in geometry literally at every step. There are about five hundred different proofs of this theorem, which shows the huge number of its specific implementation