Answer
Answers may vary. An example is below.
Work Step by Step
We need a function whose denominator equals 0 when x equals 8. We choose $2x+16$. Now, we find:
$$\frac{k}{2}=3 \\k=6$$
Thus, the numerator's coefficient is 6. This means:
$$ \frac{6x}{2x+16}$$