To evaluate $f(8)$ graphically using the provided image:

1. Look for the $x$-coordinate of 8 on the graph.
2. Locate the corresponding point on the function. From the graph:
   • The open circle at $(8, -3)$ means that $f(8)$ is not defined at $y = -3$.
   • The filled circle at $(8, -6)$ indicates the actual value of the function at $x = 8$.

Thus, $f(8) = -6$.

Would you like further clarification or details on this?
Here are five related questions for practice:

1. How do open and closed circles affect the value of a function?
2. How can you determine if a function is continuous at a given point?
3. What does $f(a)$ represent graphically?
4. How can you evaluate $f(x)$ for other points using this graph?
5. What is the difference between evaluating $f(8)$ and finding the limit as $x \to 8$?

Tip: Always check whether the point is included (closed circle) or excluded (open circle) when interpreting a graph!