We have <span>v(x)=54x^3+264x^2-738x+420 , and the sum of coefficients are 54+264-738+420=0, so 1 is a zero of v(x), it means v(1)=0 so v(x) can be written as v(x)= (x-1) Q(x) and obviously, Q(x) = v(x) / (x-1) </span>Q(x)=54x^3+264x^2-738x+420/(x-1)= (6x+42)(9x-10) v(x)=(x-1)(6x+42)(9x-10) <span> the volume of rectangular prism is V= LxWxH we can assume tha L=x-1, W=6x+42 and H= 9x-10