We know that is less than , which means that:
Substitute and add:
You know that:1.) Express the area A(x), of the rectangle as a function of X.
And there it is.
Well has to be greater than 0, and that is less than 8.2.) Determine the domain of A(x).
3.) Approximate the maximun area of the rectangle and state the dimensions of the rectangle.
So A(x) is between zero and sixty-four.