OK, I've been killing myself over this one problem and I just cannot seem to get it. :grumpy: I know it's probably a lot easier than I'm making it out to be. If anyone can give me a little help I would really appreciate it. Here's the question: If 1200cm^2 of material is available to make a box with a square base and an open top, what is the box's larget possible volume? So far, I'm guessing that since the base of the box is to be square and there's an open top, the area of the box = x^2 + 4xy = 1200 and the volume = (x^2)y. I know at some point I'll need to differentiate and find the maximum of the function, but, I'm sort of floundering at this point. Thanks in advance.