college algebra
posted by Missy .
A propane tank has the shape of a circular cylinder with a hemisphere at each end. The cylinder is 6 feet long and volume of the tank is 5pie cubic feet. Find, to the nearest thousandth of a foot the length of the radius x.

with radius x,
v = (pi * x^2 * h) + (4/3 * pi * x^3)
5pi = (pi*x^2*6) + (4/3 pi * x^3)
4/3 x^3 + 6x^2  5 = 0
4x^3 + 18x^2  15 = 0
x = 0.838