Answer:

Explanation:
The domain of a rational function is all real numbers except for when the denominator equals 0.
So, to find the domain restrictions, set the denominator to 0 and solve for x.
We have the rational function:

Set the denominator to 0:

Subtract 9:

So, the domain is all real numbers except for -9.
In other words, our domain is all values to the left of negative 9 and to the right of negative 9.
In interval notation, this is:

And we're done :)