Which best summarizes the pythagorean theorem

The Pythagorean Theorem says that the square of the longest side—the hypotenuse—of a right triangle is equal to the sum of the squares of the two other legs.

Mathematically, we write
,
where c is the length of the hypotenuse, and a and b are each of the two legs.

3x+9+4x+x=8x+9that's the answer for your question.