A farmer has 140ft of fencing with which she will enclose a rectangular region adjacent to a barn 6ft long. If she insists on using the entire length of the barn as a portion of one side of the rectangle, what is the maximum area that may be enclosed?

Question

jack1 · Answer

so when is area greatest in a rectangle?

jack1 · Answer

and from that, you know L x W = Area
and you have worked out L 
and are given W
so Area = ???  (square feet)

anonymous · Answer

Hey, sorry I had to run to the store quick. Just reading what you said quickly

anonymous · Answer

length= 64 and area=384

jack1 · Answer

ahh.. close... try length again

anonymous · Answer

I had a typo sorryl length is 67 and area is 402

jack1 · Answer

sweet, spot on!

anonymous · Answer

So maximum area is 402?

jack1 · Answer

yep, if he insists on using the barn as a side

anonymous · Answer

Is there a different way of solving it? Just so that I understand better

jack1 · Answer

for that one, it's the only way of solving it as its the only area you can get
as per picture, rectangle has 2 groups of 2 equal sides
so as one side is marked as 6 ft long, the side opposite to that has to be the same length, which leaves only one variable to solve (Length)

jack1 · Answer

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