James A. Garfield, the twentieth president of the United States, discovered a proof of the Pythagorean Theorem

Question:

James A. Garfield, the twentieth president of the United States, discovered a proof of the Pythagorean Theorem in 1876. His proof involved the fact that a trapezoid can be formed from two congruent right triangles and an isosceles right triangle. Use the diagram to show that a² + b² = c².