# How do you simplify (u^2+7u-18)/(u-2) and what are the excluded values for the variables?

Apr 25, 2017

$u + 9$

$u \ne 2$

#### Explanation:

Although you have a numerator and denominator you are not allowed to simplify yet by cancelling, because there are terms (separated by + and * signs) rather than factors (which are multiplied)

Find the factors first.

$\frac{{u}^{2} + 7 u - 18}{u - 2}$

$\frac{\left(u + 9\right) \left(u - 2\right)}{\left(u - 2\right)} \text{ } \leftarrow$ now you can cancel

((u+9)cancel((u-2)))/(cancel((u-2))

$= u + 9$

For excluded values, remember that the denominator may not be equal to $0$.

So, ask yourself what value of $u$ would make $0$?

If $u - 2 = 0 \text{ } \rightarrow u = 2$