document.write( "Question 79468: A flat piece of wood with an area of 27 sq ft, and perimeter of 21 ft. How do I calculate the dimensions? I'm totally clueless. Thanks for our help. \n" ); document.write( "

Algebra.Com's Answer #57032 by Nate(3500) $\"\"$ $\"About$

You can put this solution on YOUR website!
I don't know what shape the flat piece of wood is. I would assume it as a rectangle or a square.
\n" ); document.write( "lenght = l
\n" ); document.write( "width = w
\n" ); document.write( "2w + 2l = 21
\n" ); document.write( "and
\n" ); document.write( "lw = 27 or l = 27/w
\n" ); document.write( "Plug:
\n" ); document.write( "2w + 2l = 21
\n" ); document.write( "2w + 2(27/w) = 21
\n" ); document.write( "2w^2 + 54 = 21w
\n" ); document.write( "2w^2 - 21w + 54 = 0
\n" ); document.write( "2w^2 - 9w - 12w + 54 = 0
\n" ); document.write( "(2w^2 - 9w) + (-12w + 54) = 0
\n" ); document.write( "w(2w - 9) - 6(2w - 9) = 0
\n" ); document.write( "(w - 6)(2w - 9) = 0
\n" ); document.write( "w = 6
\n" ); document.write( "or
\n" ); document.write( "w = 9/2 = 4.5
\n" ); document.write( "The rest is explanatory. \n" ); document.write( "

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