An open box with a square base is required to have a volume of 10 cubic feet.

Question

Express the amount (A) of the material used to make such a box as function of the length of (x) of a side of the square base. 

Answer 1

V = x²h

10 = x²h

10/x² = h

A = x² + 4(xh)

A = x² + 4(x(10/x²))

A = x² + 4(10/x)

A = x² + 40/x