an open box is made from a sheet of metal (12in x 16in), by cutting equal squares of side x from each corner.

a) write an expression for the volume of the box.
b) graph the function. find the maximum volume that can be contained by the box.


help?

Sketch a 12 by 16 rectangle on a sheet of paper, and cut out 4 square corners, the sides of which are x inches long. Now fold up the edges to form a container of height (h) = x, length (l) = 16 - 2x, and width (w) = 12 - 2x.
Since V = lwh, can you multiply these terms together to get an expression for V? Have you had calculus yet to determine the maximum V?