Answer: f(5)=9.5
Explanation:
If the graph displays f(x)=(-1/2)x+12, then the answer for f(5) would be 9.5.
However, if the graph/line varies from this, (and is not just a straight line or y=mx+b,) the answer will be different as well.
Given the information you gave me though, this is the best I can do. Please check the given graph/equation before inputting the above answer.