The graph of $y=8$ is a horizontal line because all points on its graph have a y-coordinate of $8$. Connecting these points forms a horizontal line.
Work Step by Step
The equation $y=8$ means the points on the graph can have any x-value as long as their y-coordinate is $8$. Thus, the points $(0, 8)$, $(1, 8)$, $(-1, 8)$, and $(-2, 8)$ are all on the graph of $y=8$. Plotting these points would show that when connected, a horizontal line is formed.