MATH ANALYSIS
posted by anonymous .
How should this be done?
Suppose you have 132 m of fencing with which to make two sidebyside rectangular enclosures against an existing wall. if the rectangular enclosures are adjacent and of the same depth what is the maximum are that can be enclosed?

Draw a diagram!
You will need three cross fences, and one that is parallel to the wall.
Let the length of each cross fence be x.
Express the length L of the longitudinal fence in terms of x and 132 m.
Express the total area A(x) of the two rectangular areas in x and L, and subsequently in x only.
Use calculus to maximize A(x). Solve for x.