Question 875242:  The polynomial x 3  + 5x 2  -57x -189 expresses the volume, in cubic inches, of a shipping box, and the width is (x+3) in.  If the width of the box is 15 in., what are the other two dimensions? ( Hint: The height is greater than the depth.)
 
  A. 
height: 19 in.
 
depth: 5 in.
 
  B. 
height: 21 in.
 
depth: 5 in.
 
  C. 
height: 19 in.
 
depth: 7 in.
 
  D. 
height: 21 in.
 
depth: 7 in. 
 Answer by ewatrrr(24785)      (Show Source): 
You can  put this solution on YOUR website!    
Hi 
x^3 + 5x^2 -57x -189 = 0 (x+3) a factor, x = -3, a root 
Using Synthetic Division 
-3	1	5	-57	-189 
		-3	-6	189 
	1	2	-63	0 
x^2 + 2x - 63 = 0 
(x + 9)(x-7) = 0 
(x+9)and (x+7)the height and depth(height greater than depth) 
 (x+3)= 15 ,  x = 12 
the height = (x+9) = 21, depth is (x-7) = 5 
B. 
  
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