document.write( "Question 1001420: Nicky has 120 feet of fence to put around a rectangular garden. if a 10 foot opening is left on one side for a gate. what would be the length and width for maximum area? L=20 ft w=20 ft \n" ); document.write( "
Algebra.Com's Answer #618604 by josgarithmetic(39617)\"\" \"About 
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A square shape will give maximum area. I do not give that analysis here. The perimeter of this would be \"120%2B10\", to include both the fence and the gate(unfenced). Cut the 130 feet into four equal parts, and this is the side of the square garden.\r
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\n" ); document.write( "\n" ); document.write( "\"32%261%2F2\" feet square.\r
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\n" ); document.write( "MAXIMIZE AREA\r
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\n" ); document.write( "\n" ); document.write( "Dimensions are x and y.
\n" ); document.write( "The entire perimeter of the garden is length_of_fencing PLUS 10 feet for gate; so this means the perimeter of the garden is \"120%2B10=130\" feet.\r
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\n" ); document.write( "\n" ); document.write( "Two basic equations are needed.
\n" ); document.write( "\"system%282x%2B2y=130%2CA=xy%2CA=AreaOfGarden%29\".\r
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\n" ); document.write( "\n" ); document.write( "Use these to make a function A dependent on just ONE of the variables, either x or y.\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2B2y=130\"
\n" ); document.write( "\"x%2By=65\"
\n" ); document.write( "\"y=65-x\"
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\n" ); document.write( "\"A=xy\"
\n" ); document.write( "\"highlight%28A=x%2865-x%29%29\"------Area A is a function of the dimension, x, a quadratic function, and you can look for the MAXIMUM. You know there is a maximum because the coefficient on \"x%5E2\" will be negative...
\n" ); document.write( "The max area will occur in the exact middle of the roots or zeros or x-intercepts of \"A%28x%29\".
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\n" ); document.write( "Solve for the x-intercepts.
\n" ); document.write( "\"A%28x%29=0=x%2865-x%29\"\r
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\n" ); document.write( "\n" ); document.write( "The roots are 0 and 65.
\n" ); document.write( "The value for x exactly in the middle is \"%280%2B65%29%2F2=65%2F2=32%261%2F2\".\r
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\n" ); document.write( "\n" ); document.write( "WHAT IS THE VALUE FOR y FOR THIS VALUE OF x ?
\n" ); document.write( "WHAT IS THE AREA AT THIS VALUE OF x ?
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