A rectangular area is to be enclosed and divided into thirds. The family has $440 to spend for the fencing material. The outside fence costs $10 per foot installed, and the dividers cost $20 per foot installed. Let x represent the length (in feet) of a side perpendicular to the dividers, and let y represent the length (in feet) of a side parallel to the dividers. Write an equation that represents the area of the enclosed rectangle in terms of the variable y. A(y) = Find A"(y). A"(y) = What are the dimensions (in ft) that will maximize the area enclosed? (The answer contains a fraction.) a side parallel to the dividers ft a side perpendicular to the dividers. ft