document.write( "Question 1150376: a rug measuring 9m by 12m was installed in a recreational hall. A strip of floor of equal width was left uncovered along all edges of the hall. the area of the uncovered floor is 270m^2. how wide is the uncovered strip \n" ); document.write( "

Algebra.Com's Answer #771758 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "The area of the uncovered floor = (9+2x)*(12+2x) - 9*12 = 4x^2 + 42x.\r\n" );
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document.write( "The equation to find the uniform strip width is\r\n" );
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document.write( "    4x^2 + 42x = 270  square meters,  or\r\n" );
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document.write( "    4x^2 + 42x - 270 = 0.\r\n" );
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document.write( "     =  = .\r\n" );
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document.write( "Only positive root  x =  = 4.5  makes sense.\r\n" );
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document.write( "ANSWER.  The uniform width of the strip is 4.5 meters.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Thanks to @MathTherapy (!)\r
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