So my sister is looking for help on a math problem and turned to me. Unfortunately I havn't done this stuff in years. Can anyone give me a refresher so I know how to explain and answer this problem for her?

Here is what she gave me:

A boxed shaped storage container with the square base and no top is to have a capacity of 38 cubic ft. The material for the bottom of the container costs 59 cents per square foot, while material for the sides costs 43 cents per square foot. You want to find the length, width, height of the container that costs the least amount.

Find the equation for the function f giving the cost as a function of a variable x. Indicate what x represents.

If you can solve it for me cool, but I can probably get it easily enough if I knew what topic to google for the refresher.