Answer:
y = -1
Step-by-step explanation:
A horizontal line has slope zero (0). Therefore its slope y-intercept form should look like:
[tex]y=mx+b\\y=(0)x +b[/tex]
Therefore, using the given point (-2, -1) be on this line implies that it satisfies its equation:
[tex](-1)=(0)*(-2)+b\\-1=b[/tex]
Therefore, the equation of the line is: [tex]y=-1[/tex]