slope-intercept form:
y= mx+b
Where:
m= slope
b= y-intercept
Apply the slope formula:

Use two coordinate points from the table:
Point 1 = (x1,y1) = (-3,-4)
Point 2 = (x2,y2) = (0,-3)
Replacing:

slope = 1/3
The y-intercept is the coordinate point where x=0 (0,-3)
b= -3
Final equation:
y= 1/3x -3