document.write( "Question 86695: Solve algebraically using only one variable. The length of a rectangle is two more than twice its width. If the area of the rectangle is 84, find the length and width. \n" ); document.write( "
Algebra.Com's Answer #62715 by praseenakos@yahoo.com(507)\"\" \"About 
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Question:\r
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\n" ); document.write( "\n" ); document.write( "Solve algebraically using only one variable. The length of a rectangle is two more than twice its width. If the area of the rectangle is 84, find the length and width.\r
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\n" ); document.write( "\n" ); document.write( "Assume that width of the rectangle = x units.(since here length is given in terms of width...so first assume width = x units)\r
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\n" ); document.write( "\n" ); document.write( "Then twice the width = 2*x = 2x\r
\n" ); document.write( "\n" ); document.write( "Two more than twice the width = 2x + 2\r
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\n" ); document.write( "\n" ); document.write( "Then length of the rectangle = 2x + x units\r
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\n" ); document.write( "\n" ); document.write( "Now area of the triangle is given as = 84\r
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\n" ); document.write( "\n" ); document.write( "By the formula, area = length * width\r
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\n" ); document.write( "\n" ); document.write( "==> length * width = 84\r
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\n" ); document.write( "\n" ); document.write( "==> (2x + 2 ) * x = 84\r
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\n" ); document.write( "\n" ); document.write( "Remove the parenthesis....\r
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\n" ); document.write( "\n" ); document.write( "==> 2x * x + 2 * x = 84\r
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\n" ); document.write( "\n" ); document.write( "==> \"+x%5E2+%2B+x+-+42+=+0+\"\r
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\n" ); document.write( "\n" ); document.write( "This is a quadratic equation....you can solve it by either factorisation method or using quadratic formula...\r
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\n" ); document.write( "\n" ); document.write( "Factorisation method....\r
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\n" ); document.write( "\n" ); document.write( "\"+x%5E2+%2B+x+-+42+=+0+\"\r
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\n" ); document.write( "\n" ); document.write( "Here you have to find out two numbers whose sum is 1 and their product is -42\r
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\n" ); document.write( "\n" ); document.write( "Such two numbers are 7 and -6\r
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\n" ); document.write( "\n" ); document.write( "Now split the middle terms using this numbers.....\r
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\n" ); document.write( "\n" ); document.write( "\"+x%5E2+%2B+7x+-+6x++-+42+=+0+\"\r
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\n" ); document.write( "\n" ); document.write( "Now group the terms....\r
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\n" ); document.write( "\n" ); document.write( "\"+%28x%5E2+%2B+7x%29+-+%286x++%2B+42%29+=+0+\"\r
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\n" ); document.write( "\n" ); document.write( "Now take out the common term from each group.....\r
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\n" ); document.write( "\n" ); document.write( "\"+x%28x+%2B+7%29+-+6%28x++%2B+7%29+=+0+\"\r
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\n" ); document.write( "\n" ); document.write( "Here (x+ 7 ) is common ib both the groups...so again take it outside...\r
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\n" ); document.write( "\n" ); document.write( "==> (x + 7)( x- 7) = 0\r
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\n" ); document.write( "\n" ); document.write( "==> either x + 7 = 0 or x - 6 = 0\r
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\n" ); document.write( "\n" ); document.write( "==> x = -7 or x = 6\r
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\n" ); document.write( "\n" ); document.write( "So the solution of the given expression is x = -7 or x = 6\r
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\n" ); document.write( "\n" ); document.write( "You can check the answers using quadratic formula, \"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"\r
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\n" ); document.write( "\n" ); document.write( "Then you will get the same answers....\r
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\n" ); document.write( "\n" ); document.write( "Hope you found the explanation useful...\r
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\n" ); document.write( "\n" ); document.write( "Warm Regards.\r
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\n" ); document.write( "\n" ); document.write( "Praseena.
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