x + y + H = 60 : perimeter , x, y and H be the two legs and the hypotenuse of the right triangle
(1/2)xy = 150 : area
x2 + y2 = H2: Pythagora's theorem.
3 equations with 3 unknowns.
(x + y)2 - 2xy = H2 : completing the square in the third equation.
x + y = 60 - H : express x + y using the first equation and use the second equation to find xy = 300 and substitute in equation 5.
(60 - H)2 - 600 = H2 : one equation with one unknown.
Solve for H to find H = 25 cm. Substitute and solve for x and y to find x = 15 cm and y = 20 cm.
