posted by John .
a box with an open top is constructed from a rectangular piece of cardboard with dimensions 14 inches by 18 inches by cutting out and discarding equal squares of side x at each corner and then folding up the sides as in the figure. The cost to create such a box is 2.50 per square foot for the bottom and 1.50 per square foot for the sides
a. Express the cost of the box as a function of x.
b. Graph c=c(x). For what value of x is C smallest?