document.write( "Question 758375: Ok. I need to find the optimum perimeter for a rectangle with the area of 242cm squared. My teacher didn't even teach us he just gave it to us and said do it. I am in grade 8. I would appreciate if you could really expand on this so I can understand. THANKS :D \n" ); document.write( "
Algebra.Com's Answer #461443 by Alan3354(69443)\"\" \"About 
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I need to find the optimum perimeter for a rectangle with the area of 242cm squared.
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\n" ); document.write( "You can find the minimum perimeter, not sure what optiumum would be.
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\n" ); document.write( "Pick a perimeter and find the max area: P = 100
\n" ); document.write( "P = 2L + 2W = 100
\n" ); document.write( "L + W = 50
\n" ); document.write( "L = 50 - W
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\n" ); document.write( "Area = L*W = W*(50 - W)
\n" ); document.write( "Area = 50W - W^2
\n" ); document.write( "W^2 - 50W + Area = 0
\n" ); document.write( "It's a quadratic in W
\n" ); document.write( "Ther vertex is on the Axis of Symmetry which is
\n" ); document.write( "W = -b/2a
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\n" ); document.write( "W = 50/2 = 25
\n" ); document.write( "L = 25
\n" ); document.write( "---> Max area of a rectangle of given perimeter is a square.
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\n" ); document.write( "For Area = 242
\n" ); document.write( "L = W = sqrt(242)
\n" ); document.write( "= \"11%2Asqrt%282%29\" cm
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