I'm stuck on how to factor this:
r^3+4r^2+7r+6=0
thanks!
You're expected to note that r = -2 is a solution to r^3+4r^2+7r+6=0 and therefore (r + 2) is a factor of r^3+4r^2+7r+6. Therefore you can find the quadratic factor of r^3+4r^2+7r+6 using polynomial long division etc.