Answer:
y=(-1/2)x-3.5
Explanation:
Using the equation (rise/run) with the two marked points, we find that the slope is (1/-2), or -1/2.
The y-intercept, as seen in the graph, is -3.5.
Once you plug the slop and y-intercept into y=mx+b, you get your equation: y=(-1/2)x-3.5
To check your answer, swap x and y out for values of a point on the line. With the point (1, -4)..:
-4=(-1/2)1-3.5
-4=(-1/2)-3.5
-4=-4