# How do you simplify and list the restrictions for h (x)= (7 - x) /( 3x - 21)?

Refer to explanation

#### Explanation:

We have that

$3 x - 21 = 0 \implies x = 7$ hence the domain is $R - \left\{3\right\}$

we have that

$h \left(x\right) = \frac{7 - x}{3 \left(x - 7\right)} = - \frac{1}{3}$