I'm not quite sure what you are asking. You might recall in geometry that the parameter of a rectangle is . You can set up the equation in several ways as you have a very broad domain. You can set up the equation in the form of minimums and maximums if this is for calculus. What class is this for? Maybe I'm just not understanding the question. Can anyone help out here?
Also, to note exponents just write the coefficient and the power with a carat (^). So in the case of x squared you'd say x^2. It's easier to read that way. If you insert the x^2 into the math brackets (it's the Sigma symbol in the reply/post "advanced" screen) it'll look like this . Hope that helps.