document.write( "Question 86483: An open-top box is to be constructed from a 4 foot by 6 foot rectangular cardboard by cutting out equal squares at each corner and folding up the flaps. Let x denote the length of each side of the square to be cut out.
\n" ); document.write( "a) Find the function V that represents the volume of the box in terms of x.
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\n" ); document.write( "\n" ); document.write( "b) Graph this function and show the graph over the valid range of the variable x..
\n" ); document.write( "Show Graph here.\r
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\n" ); document.write( "\n" ); document.write( "c) Using the graph, what is the value of x that will produce the maximum volume?
\n" ); document.write( "Answer.
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Algebra.Com's Answer #62595 by ankor@dixie-net.com(22740)\"\" \"About 
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An open-top box is to be constructed from a 4 foot by 6 foot rectangular cardboard by cutting out equal squares at each corner and folding up the flaps. Let x denote the length of each side of the square to be cut out.
\n" ); document.write( ":
\n" ); document.write( "We know from the above information:
\n" ); document.write( "Box length = (6-2x)
\n" ); document.write( "Box width = (4-2x)
\n" ); document.write( "Box height = x
\n" ); document.write( ":
\n" ); document.write( "a) Find the function V that represents the volume of the box in terms of x.
\n" ); document.write( "Answer:
\n" ); document.write( "Vol = length * width * height
\n" ); document.write( "V = (6-2x)*(4-2x)*x
\n" ); document.write( "V = x(24 - 20x + 4x^2); FOILed (6-2x)(4-2x); then mult by x
\n" ); document.write( "V = 4x^3 - 20x^2 + 24x; represents the volume of the box
\n" ); document.write( ":
\n" ); document.write( "b) Graph this function and show the graph over the valid range of the variable x..
\n" ); document.write( "Plot the value from .2 to 1.8 only; y = V
\n" ); document.write( " x | y
\n" ); document.write( "-------
\n" ); document.write( ".2 | 4.032
\n" ); document.write( ".4 | 6.656
\n" ); document.write( ".6 | 8.064
\n" ); document.write( ".8 | 8.448
\n" ); document.write( "1.0| 8.0
\n" ); document.write( "1.2| 6.912
\n" ); document.write( "etc
\n" ); document.write( ":
\n" ); document.write( "Show Graph here.
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-1%2C+2%2C+-3%2C+10%2C+4x%5E3-20x%5E2%2B24x%29+\"\r
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\n" ); document.write( "\n" ); document.write( "c) Using the graph, what is the value of x that will produce the maximum volume?
\n" ); document.write( "Answer.
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\n" ); document.write( "It looks like max volume will occur when x = .8
\n" ); document.write( ":\r
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