Question

A farmer needs to build a rectangular pen that is 800 square feet and has two bays. What equation can he use to minimize the cost of the fence and what are the dimensions of the pen?

Answer 1

xy = 800

p = 2x+3y = 2x + 2400/x

Now just find x for minimum p.

This assumes two rectangular areas sharing a common fence of length y.

Answer 2

Thanks Steve!