document.write( "Question 310541: What is the minimum perimeter possible for a rectangle with an area or 500cm squared \n" ); document.write( "
Algebra.Com's Answer #222090 by Fombitz(32388)\"\" \"About 
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Perimeter of a rectangle
\n" ); document.write( "\"P=2%2A%28L%2BW%29\"
\n" ); document.write( "Area of a rectangle
\n" ); document.write( "\"A=L%2AW=500\"
\n" ); document.write( "\"L=500%2FW\"
\n" ); document.write( "Substitute this expression into the perimeter equation,
\n" ); document.write( "P=2*(500/W+W)
\n" ); document.write( "Now perimeter is a function only of W.
\n" ); document.write( "To find the minimum, take the derivative wrt W and set it equal to zero.
\n" ); document.write( "\"P=1000%2FW%2B2W=1000W%5E%28-1%29%2B2W\"
\n" ); document.write( "\"dP%2FdW=-1000W%5E%28-2%29%2B2=2-1000%2FW%5E2=0\"
\n" ); document.write( "\"1000%2FW%5E2=2\"
\n" ); document.write( "\"W%5E2=500\"
\n" ); document.write( "\"W=sqrt%28500%29\"
\n" ); document.write( "Since \"L%2AW=500\", then
\n" ); document.write( "\"L=sqrt%28500%29\"
\n" ); document.write( "The shape that minimizes perimeter is a square of side \"sqrt%28500%29\".
\n" ); document.write( "\"Pmin=4sqrt%28500%29\"
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