To find $f(9)$, substitute $x = 9$ into the function rule $f(x) = -7 - x$.

$f(9) = -7 - 9$

Now, simplify:

$f(9) = -7 - 9 = -16$

So, $f(9) = -16$.

Would you like any further details or have any questions?

Here are 5 related questions:

1. What is $f(0)$ for the function $f(x) = -7 - x$?
2. If $f(x) = -7 - x$, what is the inverse of this function?
3. How does the graph of $f(x) = -7 - x$ look?
4. For what value of $x$ is $f(x) = 0$?
5. How would the function change if the rule was $f(x) = -7 + x$?

Tip: For linear functions like $f(x) = -7 - x$, the graph will always be a straight line, and the slope is determined by the coefficient of $x$.