### Home > PC3 > Chapter 12 > Lesson 12.2.1 > Problem12-96

12-96.

Identify all of the roots of the polynomial $p(x) = −x^{4} + 4x^{2} − 12x + 9$.

There are four roots. The rational roots will be factors of $9$.

Graph the polynomial to determine which of the possible rational roots are actual roots.
If $x = a$ is a root, then $(x − a)$ is a factor of the polynomial.
Divide out the factors.