Answer:
y = 4x + 8
Explanation:
A linear formula always follows by y = mx + c, where m is the gradient and c is the y-intercept or constant.
Since you know that the slope is 4, all you need to do is find the y-intercept (constant)
y = 4x + c
Sub in the points (-4, -8)
-8 = 4(-4) + c
-8 + 16 = c
c = 8
Hence, y = 4x + 8