Math
A rectangular enclosure is to be constructed with 800 feet of fence in order to have four sections. What should be the dimensions in order to maximize the area enclosed? What is the maximum area?
asked by
Carly

Well, I bet it turns out to be a square but anyway:
A = b c where b is breadth and c is length
2 b + 2 c = 800
so
b + c = 400
c = (400  b)
so
A = b * (400b)
A = 400 b  b^2
b^2  400 b + A = 0
where is the vertex of this parabola (I assume you do not do calculus)
b^2  400 b = A
b^2  400 b + 40,000 = A + 40,000
(b200)^2 = A + 40,00
vertex (maximum) when b = 200
then c = 400200 also = 200
just as we suspected
posted by Damon
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