document.write( "Question 255965: Can you please explain to me how to do this??\r
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document.write( "Mr. Greene has 8.5-by-11 in. cardboard sheets. As a class project, Mr. Greene asked each of his students to make an open-top box under these conditions:
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document.write( "I) Each box must be made by cutting small squares from each corner of a cardboard sheet.
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document.write( "II) The box must have a volume of 48 in^3.
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document.write( "III) The amount of cardboard waste must be minimized.
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document.write( "What is the approximate side length for the small squares that would be cut from the cardboard sheet? \n" );
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Algebra.Com's Answer #188423 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! Mr. Greene has 8.5-by-11 in. cardboard sheets. As a class project, \n" ); document.write( " Mr. Greene asked each of his students to make an open-top box under these conditions: \n" ); document.write( ": \n" ); document.write( "I) Each box must be made by cutting small squares from each corner of a cardboard sheet. \n" ); document.write( "II) The box must have a volume of 48 in^3. \n" ); document.write( "III) The amount of cardboard waste must be minimized. \n" ); document.write( "What is the approximate side length for the small squares that would be cut from the cardboard sheet? \n" ); document.write( ": \n" ); document.write( "Draw a rectangle representing the 8.5 by 11 in sheet. Cut out a small square in each corner, label the side of the square as x. \n" ); document.write( ": \n" ); document.write( "Visualize bending the sides up to form an open box; it will be apparent that \n" ); document.write( "Box dimensions will be: \n" ); document.write( "(11-2x) = box length \n" ); document.write( "(8.5-2x) = box width \n" ); document.write( "x = box height \n" ); document.write( ": \n" ); document.write( "Vol: height * Length * width \n" ); document.write( "x*(11-2x)*(8.5-2x) = 48 \n" ); document.write( "FOIL \n" ); document.write( "x(93.5 - 22x - 17x + 4x^2) = 48 \n" ); document.write( "x(93.5 - 39x + 4x^2) = 48 \n" ); document.write( "93.5x - 39x^2 + 4x^3 - 48 = 0 \n" ); document.write( "The equation \n" ); document.write( "4x^3 - 39x^2 + 93.5x - 48 = 0 \n" ); document.write( ": \n" ); document.write( "Now the easiest way, is to plot this equation on a graphing calc \n" ); document.write( " \n" ); document.write( "Note we have 3 solutions for x, the last one x=6+ is not valid but \n" ); document.write( "x = .7 and = 2.7 are, however, the removed square would be \"waste\" therefore \n" ); document.write( "x = .7 would be the smallest square, that would be the choice \n" ); document.write( " \n" ); document.write( " |