Answer:
3/1 or just 3
Explanation:
What you can do it count the units of the rise and run. You find the spot where the line is on a full coordinate, so, in this case, you could use (3,0) and then find the next spot where the line crosses a proper coordinate (-1,3), and you count the rise first, so how many units up until the coordniate: 3 units, then you count over until you're on the second coordinate: 1 unit.
I hope this helped!