Answer:
D. 2 and 5
(Just so you know, I'm not 100% sure this is right but I'm pretty sure I've answered this exact problem before)
Explanation:
You have to look at the intersection points between the two lines. The x values are going to be the solution, and in this case line g(x) intersects f(x) at (2,-1) and (5,-4) so you take the x values and have your solutions.