Answer:
y = -2
Explanation:
Since the line is horizontal, all points have the same y-coordinate, -2. The y-intercept is the point (0, -2), so b = -2. The line is horizontal, so the slope is m = 0 which is given.
Use the slope-intercept form of the equation of a line and plug in the information you have.
y = mx + b
y = 0x + (-2)
y = -2