document.write( "Question 1151179: The length of a rectangle is 1 yd less than twice the width, and the area of the rectangle is 21 yd^2. Find the dimensions of the rectangle\r
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Algebra.Com's Answer #772835 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( " You can solve the problem in much shorter way, practically in your head, without solving quadratic equation.\r
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document.write( "If W is the width, then the length is  L = (2W-1).\r\n" );
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document.write( "From the given area, you get the equation\r\n" );
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document.write( "    W*(2W-1) = 21.\r\n" );
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document.write( "Multiply both sides by 2. You will get\r\n" );
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document.write( "    2W(*2W-1) = 42.\r\n" );
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document.write( "So, the product of two numbers  (2w)  and  (2W-1) is 42 and their difference is 1.\r\n" );
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document.write( "It needs 2 seconds (and knowing the multiplication table) to guess/(to recognize)  the numbers:  2W = 7,  2W-1 = 6.\r\n" );
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document.write( "Hence, the width is 3.5 yards,  the length is 2*3.5-1 = 6 yards.    ANSWER\r\n" );
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