Using the points, we can make a system of equations:
-4 = m(-2) + b
-3 = m(1) + b —> -3 = m + b —> -3 - m = b
Substitute (-3 - m) for b:
-4 = m(-2) + (-3 - m)
-4 = -2m -3 - m
-1 = -3m
1/3 = m
Plug in the solved m value to solve for b:
-4 = (1/3)(-2) + b
-4 = -2/3 + b
-3 1/3 = b
Write your final equation:
y = 1/3x - 10/3