Answer:
Equations written in slope-intercept have the form: y = m x + b where m is the slope and b is the y intercept point. Horizontal lines have a slope of 0 (similar to a flat ground surface) and m would be 0 for these lines.
Also, the y intercept is the point through which the horizontal line would pass. In this case, the y intercept or b is -11.
The equation would then be
y = 0x + (-11)
OR
y = 0x -11
Often we write the equation without the "0x" term:
y= -11