Andrews wants to build a rectangular enclosure for his animals. One side of the pen will be against the barn so he needs no fence on that side. The other three sides will be enclosed with wire fencing if Andres has 800 feet of fencing you can find the dimensions that maximize the area of the enclosure, let be the width of the enclosure perpendicular to the barn, and let it be the length of the enclosure parallel to the barn right function for the area, a of the enclosure in terms of W.