Answer:
-2
Explanation:
Get two points that intersect that line.
(1, 5) and (2, 3)
Find the rise and run.
As we can see to get from (1,5) to (2,3), we have to go to the right by 1 and go down by 2 (in this case the movement is -2 steps).
rise/run
-2/1 = -2