document.write( "Question 171903This question is from textbook Algebra & Trigonometry
\n" ); document.write( ": This problem is in the review section about the farmer and fencing.\r
\n" ); document.write( "\n" ); document.write( "A farmer with 10,000 meters of fencing wants to enclose a rectangular field and then divide it into two plots with a fence parallel to one of the sided. What is the largest area that can be enclosed?\r
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\n" ); document.write( "\n" ); document.write( "I really have no clue even where to start by solving this problem, I have searched it and found that we need to maximize the area by using a formula that looks something like(2wx2L=?) but after applying it to my problem I came up with this formula (2Lx3W=10,000. I have no clue if I am even going in the right direction. I used the two lengths because we have two long sides, and 3 widths because there is also the dividing line of fence that has to be accounted for. Any help is appreciated.\r
\n" ); document.write( "\n" ); document.write( "Thanks,
\n" ); document.write( "Kim
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Algebra.Com's Answer #127006 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
This problem is in the review section about the farmer and fencing.
\n" ); document.write( "A farmer with 10,000 meters of fencing wants to enclose a rectangular field and then divide it into two plots with a fence parallel to one of the sides. What is the largest area that can be enclosed?
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\n" ); document.write( "Farmers always want to complicate things, it seems.
\n" ); document.write( "Call W the Width and L the Length with 3 pieces.
\n" ); document.write( "The total length will be 2W + 3L
\n" ); document.write( "The Area is L*W
\n" ); document.write( "so,
\n" ); document.write( "A = L*W
\n" ); document.write( "2W+3L = 10000
\n" ); document.write( "Solve for L
\n" ); document.write( "3L = 10000-2W
\n" ); document.write( "L = (10000-2W)/3
\n" ); document.write( "sub for L into the first eqn
\n" ); document.write( "A = L*W
\n" ); document.write( "A = W*(10000-2W)/3
\n" ); document.write( "A = (10000W - 2W^2)/3
\n" ); document.write( "Now, to find the max, set the 1st derivative = 0. I don't know if you know what that means, but...
\n" ); document.write( "dA/dW = 10000/3 - 4W/3 = 0
\n" ); document.write( "10000 - 4W = 0
\n" ); document.write( "W = 2500 meters
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\n" ); document.write( "Solve for L
\n" ); document.write( "2W+3L = 10000
\n" ); document.write( "5000 + 3L = 10000
\n" ); document.write( "3L = 5000
\n" ); document.write( "L = 1667 meters
\n" ); document.write( "Area = 2500*5000/3 =~ 4,166,666.67 sq meters
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\n" ); document.write( "Making just a square would have enclosed 5000*5000 = 25,000,000 sq meters, the max area of a rectangle with a given perimeter.
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