document.write( "Question 712929: Peter has a piece of metal 18 inches wide and 20 inches long, he wants to make an open box with a volume of 200 inches cubed, by cutting out a square of the same size from each corner and folding up the edges of the piece of metal. To the nearest tenth of an inch what is the length(s) of a side of the square cut from each corner? Round to the nearest hundredths \n" ); document.write( "
Algebra.Com's Answer #438221 by ankor@dixie-net.com(22740)\"\" \"About 
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Peter has a piece of metal 18 inches wide and 20 inches long, he wants to make an open box with a volume of 200 inches cubed, by cutting out a square of the same size from each corner and folding up the edges of the piece of metal.
\n" ); document.write( " To the nearest tenth of an inch what is the length(s) of a side of the square cut from each corner
\n" ); document.write( ":\"
\n" ); document.write( "Let x = length of the side of the square to be removed from each corner
\n" ); document.write( "then
\n" ); document.write( "(20-2x) = the length of the box
\n" ); document.write( "(18-2x) = the width of the box
\n" ); document.write( "x = the height of the box
\n" ); document.write( ":
\n" ); document.write( " h * L * W = V
\n" ); document.write( " therefore
\n" ); document.write( "x(20-2x)(18-2x) = 200
\n" ); document.write( "FOIL
\n" ); document.write( "x(360 - 40x - 36x + 4x^2) = 200
\n" ); document.write( "x(360 - 76x + 4x^2) = 200
\n" ); document.write( "360x - 76x^2 + 4x^2 - 200 = 0
\n" ); document.write( "4x^3 - 76x^2 + 360x - 200 = 0
\n" ); document.write( "simplify, divide by 4
\n" ); document.write( "x^3 - 19x^2 + 90x - 50 = 0
\n" ); document.write( "find the 0 by graphing
\n" ); document.write( " \"+graph%28+300%2C+200%2C+-2%2C+4%2C+-100%2C+100%2C+x%5E3+-+19x%5E2+%2B+90x+-+50%29+\"
\n" ); document.write( "x intercept occurs when x = .64 inches, the side of of the removed square
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "You can confirm this yourself by finding the volume
\n" ); document.write( "(20-1.28)*(18-1.28) * .64 = \n" ); document.write( "
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