The equation $y = -1$ represents a horizontal line that crosses the y-axis at $y = -1$. Since the value of $y$ is always $-1$, no matter the value of $x$, the line is parallel to the x-axis.

Steps to plot the line:

1. Choose two values for $x$. For simplicity, let's pick $x = 0$ and $x = 2$.
2. For both values of $x$, the value of $y$ is always $-1$.
   • When $x = 0$, $y = -1$, so the point is $(0, -1)$.
   • When $x = 2$, $y = -1$, so the point is $(2, -1)$.
3. Plot these two points: $(0, -1)$ and $(2, -1)$.
4. Draw a straight line through these two points.

The line will be horizontal, at a constant value of $y = -1$.

Would you like me to explain any steps further, or would you like to explore something else? Here are 5 related questions:

1. What is the general form of the equation of a horizontal line?
2. How can you find the slope of a horizontal line?
3. What happens to the graph of $y = -1$ when you add a number to it, like $y = -1 + 3$?
4. How does a vertical line differ from a horizontal line in terms of equations and graphs?
5. How can you graph the equation $y = 2x + 3$?

Tip: For horizontal lines, the equation will always be in the form $y = c$, where $c$ is a constant.