We are expected to be familiar with two theorems . . .Factor: .
Answer: . .
What is the procedure?
 The rational roots of a polynomial are of the form
. . .where is a factor of the constant term and is a factor of the leading coefficient.
Our polynomial has a constant term 10 with factors: .
. . and leading coefficient 1 with factors: .
Hence, the only possible rational roots are: .
 If , then is a factor of
We find that: .
. . Hence, is a factor.
Using long or synthetic division: .
. . And that quadratic factors: .