document.write( "Question 1150427: Question 9: A rancher has 600 feet of fencing to put around a rectangular field and then subdivide the field into 3 identical smaller rectangular plots by placing two fences parallel to one of the field's shorter sides. Find the dimensions that maximize the enclosed area. Write your answers as fractions reduced to lowest terms. \n" ); document.write( "
Algebra.Com's Answer #771804 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
Let \"+w+\" = the width of the rectangle
\n" ); document.write( "\"+4w+\" = the total of the \"+w+\" lengths of fence
\n" ); document.write( "\"+%28+600+-+4w+%29+%2F+2+\" = the length of the rectangle
\n" ); document.write( "Let \"+A+\" = the total area of the rectangle
\n" ); document.write( "----------------------------------------------------------
\n" ); document.write( "\"+A+=+4w%2A%28+%28+600+-+4w+%29+%2F+2+%29+\"
\n" ); document.write( "\"+A+=+2w%2A%28+600+-+4w+%29+\"
\n" ); document.write( "\"+A+=+-8w%5E2+%2B+1200w\"
\n" ); document.write( "This is a parabola with a maximum peak
\n" ); document.write( "\"+w%5Bpk%5D+=+-1200%2F%282%2A%28-8%29%29+\"
\n" ); document.write( "\"+w%5Bpk%5D+=+75+\"
\n" ); document.write( "Plug this result back into equation
\n" ); document.write( "\"+A+=+-8w%5E2+%2B+1200w\"
\n" ); document.write( "\"+A%5Bmax%5D+=+-8%2A75%5E2+%2B+1200%2A75\" ( formula for vertex of parabola )
\n" ); document.write( "\"+A%5Bmax%5D+=+-45000+%2B+90000+\"
\n" ); document.write( "\"+A%5Bmax%5D+=+45000+\"
\n" ); document.write( "---------------------------------------
\n" ); document.write( "\"+45000%2Fw%5Bpk%5D+=+45000%2F75+\"
\n" ); document.write( "\"+45000%2Fw%5Bpk%5D+=+600+\"
\n" ); document.write( "---------------------------------------
\n" ); document.write( "The dimensions that maximize area are:
\n" ); document.write( "75' x 600'
\n" ); document.write( "----------------
\n" ); document.write( "check:
\n" ); document.write( "\"+graph%28+400%2C+400%2C+-20%2C+200%2C+-5000%2C+50000%2C+-8x%5E2+%2B+1200x+%29+\"
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