Answer:
y = -1
Explanation:
First, you find the slope by using the slope formula and get 0. Now, choose one coordinate and plug it into the equation y = mx + b along with the slope. If you chose the first coordinate, the equation would be -1 = (0)(5) + b. After solving for b (the y-intercept) you would get -1. Lastly, you rewrite the equation as y = -1.