document.write( "Question 126609: the length of a rectangle is 7 feet more than width. if the length were decreased by 3 feet and the width were increased by 2 feet, the perimeter would be 32 feet. Find the length of the original rectangle. \n" ); document.write( "
Algebra.Com's Answer #92772 by solver91311(24713)\"\" \"About 
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The length of the original rectangle is L, and the width is W. We also know that \"L=W%2B7\".\r
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\n" ); document.write( "\n" ); document.write( "If we decrease the length by 3 we get \"L-3\", and if we increase the width by 2, we get \"W%2B2\".\r
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\n" ); document.write( "\n" ); document.write( "The perimeter of a rectangle is given by \"P=2L%2B2W\", but we only know the perimeter of the new rectangle, so we have to use \"P%5Bn%5D=2%28L-3%29%2B2%28W%2B2%29=32\". But while we're at it, let's substitute \"W%2B7\" for L so that we have a single equation in a single unknown. \"P%5Bn%5D=2%28%28W%2B7%29-3%29%2B2%28W%2B2%29=32\"\r
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\n" ); document.write( "\n" ); document.write( "Now collect terms and solve:
\n" ); document.write( "\"2W%2B8%2B2W%2B4=32\"
\n" ); document.write( "\"4W%2B12=32\"
\n" ); document.write( "\"4W=20\"
\n" ); document.write( "\"W=5\"\r
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\n" ); document.write( "\n" ); document.write( "Since W is 5, L must be 5 + 7 = 12.\r
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\n" ); document.write( "\n" ); document.write( "Check:
\n" ); document.write( "If we decrese the length by 3, we get 9, and if we increase the width by 2 we get 7. (2 * 9) + (2 * 7) = 18 + 14 = 32. Answer checks.
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