The answer is y= -1
When the slope is 0, we refer to the line as a constant function. In slope intercept form, the line is equal to y = mx + b
"m" is the slope, and "b" is the y-intercept.
Let's replace those in the function.
y = 0*x - 1
0 multiplied by anything is 0
y = 0 - 1
y = -1
