Question 307808
x(18 - 2x) = 36


18x - 2x^2 - 36 = 0


x^2 - 9x + 18 = 0


(x - 6)(x - 3) = 0


x = 6 ___ OR ___ x = 3


the gutter can be 6 X 6 or 3 X 12



FYI ___ max cross section for 18" of material is 40½ sq in ___ 4½ deep X 9 wide