document.write( "Question 1195548: Sabrina is building a garden against the back wall of her house. She needs to put mesh fence
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Algebra.Com's Answer #828071 by ikleyn(52781)\"\" \"About 
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document.write( "Since one side is back wall of the house, the rectangle's fence perimeter will be\r\n" );
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document.write( "L + 2W = 60 meters.\r\n" );
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document.write( "where L is the dimension along the wall and W is the dimension perpendicular to the wall.\r\n" );
document.write( "Hence, L = 60 - 2W meters.\r\n" );
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document.write( "    Area = Length * Width.\r\n" );
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document.write( "Substitute (60-2W) for L:\r\n" );
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document.write( "    A = W(60 - 2W)       (1)\r\n" );
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document.write( "    A = -2W^2 + 60W.\r\n" );
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document.write( "It is a quadratic function. It has the maximum at x = -b/(2a), where \"a\"  is the coefficient at the quadratic term \r\n" );
document.write( "and  \"b\"  is the coefficient at the linear term, according to the general theory.\r\n" );
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document.write( "    (See the lessons\r\n" );
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document.write( "         - HOW TO complete the square to find the minimum/maximum of a quadratic function\r\n" );
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document.write( "         - Briefly on finding the minimum/maximum of a quadratic function\r\n" );
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document.write( "     in this site).\r\n" );
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document.write( "In your case, the maximum is at\r\n" );
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document.write( "    W = \"-60%2F%282%2A%28-2%29%29\" = \"%28-60%29%2F%28-4%29\" = 15.\r\n" );
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document.write( "So,  W = 15 meters is the dimension perpendicular to the wall of the house. \r\n" );
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document.write( "Then the length is  L = 60 - 2W = 60 - 2*15 = 30 meters.\r\n" );
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document.write( "Find the max area. It is \r\n" );
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document.write( "    A = L*W = 30*15 = 450 square meters.    It is the maximum area.\r\n" );
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document.write( "ANSWER.  The dimensions are 30 m along the wall and 15 m perpendicular to the wall\r\n" );
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document.write( "         The maximum area is 450 m^2.\r\n" );
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\n" ); document.write( "\n" ); document.write( "My other lessons in this site on finding the maximum/minimum of a quadratic function are \r
\n" ); document.write( "\n" ); document.write( "    - HOW TO complete the square to find the minimum/maximum of a quadratic function\r
\n" ); document.write( "\n" ); document.write( "    - Briefly on finding the minimum/maximum of a quadratic function\r
\n" ); document.write( "\n" ); document.write( "    - HOW TO complete the square to find the vertex of a parabola\r
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\n" ); document.write( "\n" ); document.write( "    - A rectangle with a given perimeter which has the maximal area is a square\r
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\n" ); document.write( "\n" ); document.write( "    - A farmer planning to fence a rectangular garden to enclose the maximal area\r
\n" ); document.write( "\n" ); document.write( "    - A rancher planning to fence two adjacent rectangular corrals to enclose the maximal area\r
\n" ); document.write( "\n" ); document.write( "    - Finding the maximum area of the window of a special form \r
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