A rectangular plot of farmland will be bounded on one side by a river and on the other three sides by a single-strand electric fence. With 800 m of wire at your disposal, what is the largest area you can enclose, and what are its dimensions?

Question

anonymous · Answer

@jbovey , please help if you can. Thanks.

phi · Answer

this is calculus,I assume
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anonymous · Answer

Yes, its calc

phi · Answer

take the derivative, set to 0, and solve for x  (and then y)

note that the 2nd derivative is negative,so this is a maximum value for the area

anonymous · Answer

Ok, do u mind giving me a min to solve. So you can tell me if im right or not?

anonymous · Answer

x= 20
y =760

is that correct?

phi · Answer

how did you get x?

anonymous · Answer

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