document.write( "Question 309443: The volume of an open box with a square base and rectangular sides us 250 cubed inches. if sides are double thickness and the bottom is triple thickness, what size box will use the least amount of material? \n" ); document.write( "
Algebra.Com's Answer #221371 by ankor@dixie-net.com(22740)\"\" \"About 
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The volume of an open box with a square base and rectangular sides us 250 cubed inches.
\n" ); document.write( " if sides are double thickness and the bottom is triple thickness, what size box will use the least amount of material?
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\n" ); document.write( "Surface area of an open box with a square base
\n" ); document.write( "x = side of the square base
\n" ); document.write( "h = height of the box
\n" ); document.write( "S.A = x^2 + 4(x*h)
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\n" ); document.write( "Surface area required with a triple thickness bottom and double thickness sides
\n" ); document.write( "S.A. = 3x^2 + 8(x*h)
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\n" ); document.write( "Vol = x^2*h
\n" ); document.write( "x^2*h = 250
\n" ); document.write( "h = \"250%2Fx%5E2\"
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\n" ); document.write( "S.A = 3x^2 + 8(x*h)
\n" ); document.write( "Substitute for h
\n" ); document.write( "S.A. = 3x^2 + 8(x*\"250%2Fx%5E2\")
\n" ); document.write( "S.A. = 3x^2 + 8(\"250%2Fx\")
\n" ); document.write( "S.A. = 3x^2 + \"2000%2Fx\"
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\n" ); document.write( "Plot this equation
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-6%2C+16%2C+-200%2C+1000%2C+3x%5E2+%2B+%282000%2Fx%29+%29+\"
\n" ); document.write( "You can see min material for surface area occurs when x = 7
\n" ); document.write( "Find the height
\n" ); document.write( "h = \"250%2F7%5E2\"
\n" ); document.write( "h = 5.1 inches
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\n" ); document.write( "Least amt of material used in a 7 by 7 by 5.1 inch box
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