you have 288 feet of fencing to enclose a rectangular plot that borders on a river. if you do not fence the side along the river, what is the largest area that can be enclosed?

Question

anonymous · Answer

it needs to look like a square

anonymous · Answer

or as close as a square as it can get

anonymous · Answer

so 96 on the 3 sides

anonymous · Answer

first the answer
take half of the fence and put it parallel to the river
other remaining half gets split between the two sides

anonymous · Answer

@haha1231233123 unfortunately that is not right

anonymous · Answer

and the area of the square is 96 times 96 = 9216.sqft

anonymous · Answer

wouldn't you use a = 2w + l ?

anonymous · Answer

144 by 72

anonymous · Answer

you have $$2x+y=288$$ so $y=288-2x$ and 
$$A=xy$$ so $$A(x)=x(288-2x)=288x-2x^2$$

anonymous · Answer

max is at the vertex, and first coordinate of the vertex is $-\frac{b}{2a}=\frac{288}{4}=72$  as promised