Roberto C. answered 05/22/13
Tutor
5.0
(178)
Highly Qualified Teacher - Algebra, Geometry and Spanish
Organize your polynomial in 2 groups:
(3p^3 - 21p^2) - (p - 7)
Now, factor the first group by GCF:
3p^2(p - 7) - (p - 7)
Notice that (p - 7) is a common factor, then factor again by GCF:
(p - 7)(3p^2 - 1)
Finally, rearrange your answer: (3p^2 - 1)(p - 7)