document.write( "Question 668721: I need help with setting up the function. Thanks.
\n" ); document.write( "A developer wants to enclose a rectangular grassy lot that borders a city street for parking. If the developer has 328 feet of fencing and doesn’t fence the side along the street, what is the largest area that can be enclosed?\r
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Algebra.Com's Answer #415826 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
This is like fencing in a rectangle, then removing one side
\n" ); document.write( "Let \"+A+\" = the area enclosed
\n" ); document.write( "Let \"+y+\" = the side parallel to the street
\n" ); document.write( "Let \"+x+\" = the length of a side perpendicular to the street
\n" ); document.write( "The amount of fencing is \"+y+%2B+2x+\"
\n" ); document.write( "(1) \"+y+%2B+2x+=+328+\"
\n" ); document.write( "The area enclosed is
\n" ); document.write( "(2) \"+A+=+x%2Ay+\"
\n" ); document.write( "----------------
\n" ); document.write( "(1) \"+y+=+328+-+2x+\"
\n" ); document.write( "By substitution:
\n" ); document.write( "(2) \"+A+=+x%2A%28+328+-+2x+%29+\"
\n" ); document.write( "(2) \"+A+=+-2x%5E2+%2B+328x+\"
\n" ); document.write( "Because of the minus sign in front of the squared term, the equation
\n" ); document.write( "has a maximum and not a minimum
\n" ); document.write( "(2) \"+A+=+x%2A%28+-2x+%2B+328+%29+\"
\n" ); document.write( "The maximum occurs halfway between the 2 roots
\n" ); document.write( "One root is at \"+x+=+0+\"
\n" ); document.write( "and to find the other root,
\n" ); document.write( "\"+-2x+%2B+328+=+0+\"
\n" ); document.write( "\"+2x+=+328+\"
\n" ); document.write( "\"+x+=+164+\"
\n" ); document.write( "Half way between is \"+x+=+82+\"
\n" ); document.write( "and, \"+y+=+328+-+2x+\"
\n" ); document.write( "\"+y+=+328+-+2%2A82+\"
\n" ); document.write( "\"+y+=+328+-+164+\"
\n" ); document.write( "\"+y+=+164+\"
\n" ); document.write( "and, at the maximum,
\n" ); document.write( "(2) \"+A+=+x%2Ay+\"
\n" ); document.write( "(2) \"+A+=+82%2A164+\"
\n" ); document.write( "(2) \"+A+=+13448+\" ft2
\n" ); document.write( "---------------------
\n" ); document.write( "Here's the plot with \"+A+\" on the vertical axis
\n" ); document.write( "and \"+x+\" on the horizontal axis
\n" ); document.write( "\"+graph%28+400%2C+400%2C+-50%2C+200%2C+-3000%2C+15000%2C+-2x%5E2+%2B+328x+%29+\"\r
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