The correct statement that explains the Pythagorean Theorem is:
If a triangle is a right triangle, then the sum of the squares of the legs is equal to the square of the hypotenuse.
This can be expressed mathematically as \(a^2 + b^2 = c^2\), where \(c\) is the length of the hypotenuse, and \(a\) and \(b\) are the lengths of the other two sides (legs) of the triangle.