document.write( "Question 825456: Hi, I really appreciate if you could help me with following math problem. Thanks!! \r
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document.write( "A farmer has 216 feet of fencing and wants to build two identical pens for his price-winning pigs.The pens will be arranged as shown. Determine the dimensions of a pen that will maximize its area. The solution is given, it would be 27' x 36'.
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document.write( "[ | ] these two pens share 1 side, the middle one; x is the width and y represents the length.\r
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document.write( "I just can't figure out how to solve it. \r
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document.write( "I reckon that the perimeter 216= 3x+ 2y and the area A= x times 2y.
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document.write( "I figured out that in this case y= 108 - (3x/2).
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document.write( "-> A= 2*(108- (3x/2)* x
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document.write( " = (216-3x)*x
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document.write( " = 3x^2-216x
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document.write( " = 3 (x^2 - 72x )
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document.write( " = 3 (x^2 -72x + 1296) -1296
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document.write( " = 3 (x-36)^2 -1296 (which I though is the product maximum)\r
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document.write( "36 is one factor of 1296 and as I know one of the solutions. Therefore 27 should be the other solution but it cannot multiply with 36 to a product of 1296. That is why I'm superconfused. Please help me as quickly as possible. Thanks in advanced. \n" );
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Algebra.Com's Answer #497309 by josgarithmetic(39620)![]() ![]() ![]() You can put this solution on YOUR website! The picture or diagram is not shown to us, but your fencing formula which I would not really call as \"perimeter\", is correct, indicating that x is one of the lengths of the divider as well as one of the dimensions of the whole rectangular form. y is the other dimension of the whole rectangular form.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Your mistake only appears to be your area formulation. This should be, \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "From this, you may find no further trouble nor confusion. \n" ); document.write( " |