The equation of a line is usually in the form y=mx+b , where m is slope and b is y-intercept.
First, we need to find the slope between the two points.
m = (y2 - y1) / (x2 - x1)
m = (-5 - (-5)) / (10 - 2)
m = 0 / 8
m = 0
Because the slope is zero, we will have a horizontal line. The y-coordinate that the two points have in common is -5. So the equation of the line will be
y = -5