document.write( "Question 438648: Find the length and width of a rectangle whose perimeter is 36 feet and whose area is 80 square feet. \n" ); document.write( "
Algebra.Com's Answer #303261 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
Find the length and width of a rectangle whose perimeter
\n" ); document.write( "is 36 feet and whose area is 80 square feet.
\n" ); document.write( "------
\n" ); document.write( "Perimeter Eq: 36 = 2(L+W)
\n" ); document.write( "Area Eq; LW = 80\r
\n" ); document.write( "\n" ); document.write( "--------
\n" ); document.write( "Modify:
\n" ); document.write( "L + W = 18
\n" ); document.write( "----
\n" ); document.write( "L(18-L) = 80
\n" ); document.write( "-L^2+18L-80 = 0
\n" ); document.write( "----
\n" ); document.write( "Use The Quadratic Formula to solve for \"L\":
\n" ); document.write( "L = [-18 +- sqrt(18^2-4*-1*-80)]/(-2)
\n" ); document.write( "---
\n" ); document.write( "L = [-18 +- sqrt(4)]/-2
\n" ); document.write( "---
\n" ); document.write( "Positive solution:
\n" ); document.write( "L = [-18-2]/-2 = 10 (length)
\n" ); document.write( "---
\n" ); document.write( "Since L+W = 18, W = 8 (width)
\n" ); document.write( "==================================
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
\n" ); document.write( "=========
\n" ); document.write( " \n" ); document.write( "
\n" );