An open box is to be made from a rectangular piece of material by cutting equal squares of length x from each corner and turning up the sides. If the material is 18 inches long and 12 inches wide. What is the volume of the box as a function of x?

Answer 1

well, x is cut off both sides, and x is the box's height, so

v(x) = (18-2x)(12-2x)(x)