# How do you use the factor theorem to determine whether v+5 is a factor of v^4 + 16v^3 + 8v^2 - 725?

Dec 22, 2015

To find if v+5 is a factor then plug in v=-5 in the given polynomial, if the result obtained is zero, then it is a factor.

#### Explanation:

If $x - a$ is a factor of the polynomial $P \left(x\right)$ then by factor theorem $P \left(a\right) = 0$.

Our question we have to check if $v + 5$ is a factor of ${v}^{4} + 16 {v}^{3} + 8 {v}^{2} - 725$

${\left(- 5\right)}^{4} + 16 {\left(- 5\right)}^{3} + 8 {\left(- 5\right)}^{2} - 725$

$= 625 - 2000 + 200 - 725$

$= - 1900$

$W e \in f e r t \hat{v} + 5 i s \neg a f a c \to r .$