Answer:
N = -2M + 110
Explanation:
Use the point (70, 20) and (50, 30) to find the slope. Use rise/run.
You go down 20 and right 10, so the rise/run is -20/10 which reduces to -2.
To find the y-intercept, go to the y axis and see where the intersects it which is 110.
N = -2M + 110