Problem: An open box is constructed by starting with a rectangular sheet of metal 10 in. by 14 in. and cutting a square of side x inches from each corner. The resulting projections are folded up and the seams welded. The volume of the resulting box is:
Answer Choices:
A. 140x−48x2+4x3
B. 140x+48x2+4x3
C. 140x+24x2+x3
D. 140x−24x2+x3
E. none of these
Solution:
The dimensions are x,10−2x,14−2x.∴V=140x−48x2+4x2.