I just took the test the correct answer is 285.74 square centimeters
21.5.......:::..............:.::.::..
<span>-1/4y(2y^3 - 8)
= -1/2 y^4 + 2 y</span>
well, we know the "sum" of both angles is 90°, notice the rectangle in the corner, so we can say that the angles are simply complementary angles, thus

X+y = 2
(2*2 + 2*2)
(4 + 2*2)
(4 + 4)
= 8