We are asked to determine the equation of a horizontal line that contains the point (-9, -7). To do that we will use the general form of a line equation in slope-intercept form:
[tex]y=mx+b[/tex]
Where "m" is the slope and "b" is the y-intercept. Since the line is horizontal the slope is zero, this is:
[tex]m=0[/tex]
Replacing in the equation of the line:
[tex]y=b[/tex]
Now, we determine the value of "b" replacing the given point. This means that when x = -9 the value of "y" is -7.
[tex]-7=b[/tex]
Therefore, the equation of the line is:
[tex]y=-7[/tex]
