Answer:
Line b is parallel to the x-axis, and its equation is y = -3
Step-by-step explanation:
Line b is parallel to the x-axis as it does not have any slope (it's horizontal).
The equation of a line parallel to the x-axis is in the form y = k, where k is a constant.
Since line b is parallel to the x-axis and passes through the point (0,-3) the equation is y = -3