document.write( "Question 175327: the perimeter of a rectangle is 42m . the length of the rectangle is 3m less than twice the width . fine the length and the width of the rectangle . \n" ); document.write( "
Algebra.Com's Answer #130397 by actuary(112)\"\" \"About 
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Let l = the length of the rectangle\r
\n" ); document.write( "\n" ); document.write( "Let w = the width of the rectangle\r
\n" ); document.write( "\n" ); document.write( "2*l+2*w=42 (Equation #1)\r
\n" ); document.write( "\n" ); document.write( "l = 2*w-3 (Equation #2)\r
\n" ); document.write( "\n" ); document.write( "Substitute equation 1 for \"l\" in Equation #2\r
\n" ); document.write( "\n" ); document.write( "2*(2w-3)+2w=42\r
\n" ); document.write( "\n" ); document.write( "4*w-6+2*w=42\r
\n" ); document.write( "\n" ); document.write( "Collect like terms\r
\n" ); document.write( "\n" ); document.write( "6w=48
\n" ); document.write( "Solve for w
\n" ); document.write( "w=8\r
\n" ); document.write( "\n" ); document.write( "Substitute w=8 into Equation #1\r
\n" ); document.write( "\n" ); document.write( "2*l+2*8=42\r
\n" ); document.write( "\n" ); document.write( "2*l+16=42
\n" ); document.write( "Solve for l\r
\n" ); document.write( "\n" ); document.write( "2*l=26\r
\n" ); document.write( "\n" ); document.write( "So l=13.
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