2y + x = 50 x = 50 - 2y y = (50 - x) / 2 z = 25 z^2 + y^2 = x^2 y = (50 - x) / 2 y = (50 - (50 - 2y)) / 2 y = (50 - 50 + 2y) / 2 2y = 50 - 50 + 2y y = y x^2 = 625 + y^2 y = 18.75