A city park commission received a donation of playground equipment from a parents' organization. The area of the playground needs to be 256 square yards for the children to use it safely. The playground will be rectangular. Part I: For any given perimeter P, the rectangle that encloses the greatest area is a square. Write an equation for the area, A, in terms of the perimeter P, and the side length x. Part II: Use the equation from Part I to result to write a simple equation to find the least amount of fencing necessary for a playground with an area of 256 square yards.