The inequality is: $8-3x \le -4$. Very straightforward. Solution is $x \ge4$. Perfect.
Then the problem says to graph this inequality using the line $y=8-3x $ and $y=-4$ and show that these 2 lines produce the validity region of $x \ge4$. These two lines intersect at $(4,-4)$. However, when I graph these two lines I do NOT see that it creates a validity region of $x \ge4$. For example, the point $(4.5,-6)$ contains an $x$ value that is $\ge 4$ and is to the left of the line, and the point $(5,-6)$ has an $x$ value that is $\ge4$ and is to the right of the line.
How do I show the validity region using those 2 lines?
You look for which $x$, the line $y=8-3x$ is under the horizontal line whose equation is $y=-4$.
You will see that $x$ must be $\ge 4$.