Answer
$\color{blue}{(-\infty, -7) \cup (-7, +\infty)}$
Work Step by Step
The denominator of a rational expression is not allowed to be equal to zero as it will make the expression undefined.
Thus,
$x+7 \ne 0
\\x+7-7\ne0-7
\\x\ne -7$
The value of $x$ can be any real number except $-7$.
Therefore, the domain of the given rational expression is the set of real numbers except $-7$.
In interval notation, the domain is:
$\color{blue}{(-\infty, -7) \cup (-7, +\infty)}$
