document.write( "Question 443207: a company wishes to manufacture a box with a volume of 36 cubic feet that is open on top and is twice as long as it is wide. find the dimensions of the box produced from the minimum amount of material. \n" ); document.write( "
Algebra.Com's Answer #305902 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
On thinking this over last night, I discovered a big error in this, let me correct it here
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\n" ); document.write( "a company wishes to manufacture a box with a volume of 36 cubic feet that is open on top and is twice as long as it is wide.
\n" ); document.write( " find the dimensions of the box produced from the minimum amount of material.
\n" ); document.write( "Let x = the width
\n" ); document.write( "Let 2x = the length
\n" ); document.write( "Let h = the height
\n" ); document.write( "then
\n" ); document.write( "vol = x*2x*h
\n" ); document.write( "so we have
\n" ); document.write( "2x^2*h = 36
\n" ); document.write( "h = \"36%2F%282x%5E2%29\"
\n" ); document.write( "h = \"18%2Fx%5E2\"\r
\n" ); document.write( "\n" ); document.write( "Surface area: two ends + 1 bottom + 2 sides (no top)
\n" ); document.write( "S.A. = 2(x*h) + 1(2x*x) + 2(2x*h)
\n" ); document.write( ":
\n" ); document.write( "I am truly sorry for this error. Carl
\n" ); document.write( ":
\n" ); document.write( "S.A. = 2xh + 2x^2 + 4xh
\n" ); document.write( "S.A. = 2x^2 + 6xh
\n" ); document.write( "Replace h with \"18%2Fx%5E2\"
\n" ); document.write( "S.A = 2x^2 + 6x(\"18%2Fx%5E2\")
\n" ); document.write( "S.A = 2x^2 + 6(\"18%2Fx\")
\n" ); document.write( "S.A = 2x^2 + (\"108%2Fx\")
\n" ); document.write( "Graph this equation to find the value of x for minimum material
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-1%2C+5%2C+-20%2C+150%2C+2x%5E2%2B%28108%2Fx%29%29+\"
\n" ); document.write( "Min surface area when x = 3.0 is the width
\n" ); document.write( "then
\n" ); document.write( "2(3) = 6 is the length
\n" ); document.write( ";
\n" ); document.write( "Find the height:
\n" ); document.write( "h = \"18%2F3%5E2\"
\n" ); document.write( "h = 2
\n" ); document.write( ":
\n" ); document.write( "Box dimensions for min surface area: 3 by 6 by 2; much better numbers
\n" ); document.write( ":
\n" ); document.write( "Check the vol of these dimensions: 3*6*2 ~ 36
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