document.write( "Question 668609: The area of a rectangle is 384 square feet. If the perimeter is 80 feet, find the length and width of the rectangle. \n" ); document.write( "
Algebra.Com's Answer #415697 by swincher4391(1107)\"\" \"About 
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A = lw
\n" ); document.write( "P = 2l + 2w\r
\n" ); document.write( "\n" ); document.write( "384 = lw
\n" ); document.write( "80 = 2l + 2w\r
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\n" ); document.write( "\n" ); document.write( "384/l = w\r
\n" ); document.write( "\n" ); document.write( "80 = 2l + 2*(384/l)\r
\n" ); document.write( "\n" ); document.write( "80l/l = (2l^2+ 2*384)/l\r
\n" ); document.write( "\n" ); document.write( "80l = 2l^2 + 768\r
\n" ); document.write( "\n" ); document.write( "2l^2-80l+768 = 0\r
\n" ); document.write( "\n" ); document.write( "2(l^2-40l + 384) = 0\r
\n" ); document.write( "\n" ); document.write( "l = 16, l =24\r
\n" ); document.write( "\n" ); document.write( "Case 1: l=16\r
\n" ); document.write( "\n" ); document.write( "If l =16 then w = 384/16 = 24\r
\n" ); document.write( "\n" ); document.write( "If l =24 then w = 384/24 = 16\r
\n" ); document.write( "\n" ); document.write( "So, we could have 16x24 or 24x16.\r
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