Mamie has 66 ft of fencing with which to enclose a rectangular dog pen. The side of her garage forms one side of the pen. Suppose the side of the pen parallel to the garage is x feet long.
(a) Express the area of the dog pen as a function of x.
(b) Find the domain of the function.
(c) Graph the function using a graphing calculator.
(d) Determine the dimensions that yield the maximum area.