The owner of a garden supply store wants to construct a fence to enclose a rectangular outdoor storage area adjacent to the store, using part of the side of the store (which is 270 feet long) for part of one of the sides. (There are 490 feet of fencing available to complete the job.
and the length of the sides parallel to the store and perpendicular that will maximize the total area of the outdoor enclosure.

Length of parallel sides
Length of perpendicular sides

I need so much help