document.write( "Question 1188666: Mr.Ulep has a rectangular field with a length twice its width.If 4 feet are taken from the length and 3 feet are taken from the width, the area of the field is 180 square feet.Find the area of the original field \n" ); document.write( "

Algebra.Com's Answer #819800 by ikleyn(52798) $\"\"$ $\"About$

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\n" ); document.write( "Mr.Ulep has a rectangular field with a length twice its width.
\n" ); document.write( "If 4 feet are taken from the length and 3 feet are taken from the width,
\n" ); document.write( "the area of the field is 180 square feet.Find the area of the original field
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document.write( "Let x be the width; then the length is 2x.\r\n" );
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document.write( "The area equation is\r\n" );
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document.write( "    (2x-4)*(x-3) = 180,\r\n" );
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document.write( "or\r\n" );
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document.write( "    (x-2)*(x-3) = 90.\r\n" );
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document.write( "    x^2 - 5x + 6 = 90\r\n" );
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document.write( "    x^2 - 5x - 84 = 0\r\n" );
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document.write( "    (x+7)*(x-12) = 0\r\n" );
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document.write( "Of the two roots, x= -7  and  x= 12, only positive value x= 12 ft is the width.\r\n" );
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document.write( "Then the length is 2*12 = 24 ft.\r\n" );
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document.write( "ANSWER.  The area of the original rectangle is 12*24 = 288 ft^2.\r\n" );
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\n" ); document.write( "\n" ); document.write( "The method shown by @shin123 is formally correct, but essentially is anti-pedagogical.\r
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\n" ); document.write( "\n" ); document.write( "Solve simple problems using simple methods.\r
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