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)![]() ![]() You can put this solution on YOUR website! I need to find the optimum perimeter for a rectangle with the area of 242cm squared. \n" ); document.write( "--------------- \n" ); document.write( "You can find the minimum perimeter, not sure what optiumum would be. \n" ); document.write( "----- \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 \n" ); document.write( "-------- \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 \n" ); document.write( "---- \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. \n" ); document.write( "======================== \n" ); document.write( "For Area = 242 \n" ); document.write( "L = W = sqrt(242) \n" ); document.write( "= \n" ); document.write( " \n" ); document.write( " |