document.write( "Question 1097599: The are of a 12m by 8m rectangle is to be doubled. By what equal amount must each dimensions be increased?
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Algebra.Com's Answer #712042 by ikleyn(52782) $\"\"$ $\"About$

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document.write( "The original area = 12*8 = 96 sq. m.\r\n" );
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document.write( "The doubled area = 96*2 = 192 sq. m.\r\n" );
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document.write( "Now I should factor 192 into the product of two factors with the difference between them equal to 12-8 = 4:\r\n" );
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document.write( "192 = 96*2 = 48*4 = 24*8 = 12*16     (!)  Ops (!!!)\r\n" );
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document.write( "Answer. The new dimensions are 16 and 12, and the increase of each dimension is 4 m.\r\n" );
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document.write( "(12+x)*(8+x) = 2*12*8,   or\r\n" );
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document.write( "x^2 + 40x - 96 = 0,\r\n" );
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document.write( "(x+36)*(x-4) = 0,\r\n" );
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document.write( "and the only positive root x= 4 is the solution to the problem.\r\n" );
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