Mark H. answered 12/07/19
Tutoring in Math and Science at all levels
You will use either long division or synthetic division to find the first 1 or 2 terms. It is a trial and error process. In this case, there a just a few options---looking at the last term, we see that there are only 3 factors: 5, 2, and 1. Each one can be + or -, so there are a total of 6 choices for the first factor.
If you have not been taught synthetic division, you can look it up with Google--or just use long division.
Try either (x - 5) or (x + 2) for the 1st factor