Question 151150:  Each of the three dimensions of a cube with a volume of y3 cubic centimeters is decreased by a whole number of centimeters. If the new volume is y3 - 13y2 + 54y - 72 cubic centimeters and the new width is y-6 centimeters, then what are the new length and height? 
 Answer by ankor@dixie-net.com(22740)      (Show Source): 
You can  put this solution on YOUR website! Each of the three dimensions of a cube with a volume of y^3 cubic centimeters is decreased by a whole number of centimeters.  
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If the new volume is y^3 - 13y^2 + 54y - 72 cubic centimeters and the new width is y-6 centimeters, then what are the new length and height? 
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Use synthetic division, divide the vol by the width 
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 6 | 1 - 13 + 54 - 72 
............+6 - 42 + 72 
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.......1 - 7 + 12 + 0 
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The quotient: y^2 - 7y + 12 
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Which factors to (y-4)(y-3) 
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The new length = +4, new height = +3 
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You can check solution: (y-6)*(y-4)*(y-3)
 
 
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