I'm working on a worksheet assigned in class, and I'm completely stumped about one problem.

My teacher never went over anything like this, and there's no a single example in my entire book of how to do this problem.

So now this is my last resort. I've uploaded an image of the problem, and I hope someone can help.

The problems with just "Find F(5)" on the graph are really simple. However, I've never seen or dealt with one like this and I don't even know where to start.