document.write( "Question 1176501: The length of a rectangle is 13 centimeters less than its width. What are the dimensions of the rectangle if its area is 90 square centimeters \n" ); document.write( "

Algebra.Com's Answer #803571 by ikleyn(52776) $\"\"$ $\"About$

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document.write( "Let w be the width, in centimeters.\r\n" );
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document.write( "Then the length is  (w+13) cm.\r\n" );
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document.write( "The area equation is\r\n" );
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document.write( "    w*(w+13) = 90.\r\n" );
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document.write( "Solve it MENTALLY by guessing:  w = 5 cm.\r\n" );
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document.write( "Or solve it formally by reducing to a quadratic equation\r\n" );
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document.write( "    w^2 + 13x - 90 = 0.\r\n" );
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document.write( "You may factor\r\n" );
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document.write( "    (w-5)*(w+18) = 0\r\n" );
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document.write( "or use the quadratic formula, on your choice.\r\n" );
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