Help with polynomials, please

A "zero," is a root of the polynomial. ie it is a value such that when one plugs it in for x, the polynomial is equal to 0. So, we know that one is a root, so we know that x-1 is a factor of of the polynomial and it happens to be a linear factor.
So use polynomial long division (or synthetic division) to find the resulting binomial. From there, (I can't do that in my head, but if I got up to get paper I could. Check the result by multiplying) use the quadratic formula, x=(-b plus or minus sqrt(b^2-4ac))/(2a). Those are the other two roots. x-r1 and x-r2 are the other two linear factors.

Hope that helps. Doing homework with a child after 5th grade gets though. Even before that it is weird because adults didn't learn it these ways we do now. Good Luck!

This will walk you through it. Its pretty complicated.

http://www.algebra.com/algebra/homework/Polynomials-and-rational-expressions/Polynomials-and-rational-expressions.faq.question.595699.html