posted by anonymous .
How should this be done?
Suppose you have 132 m of fencing with which to make two side-by-side 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.