Notice that you are given the derivative equation. That means you can calculate the slope at any given point.
So if you were to draw a line segment starting at $(0, 4)$ with slope of $−8$, what would be the coordinate point at $x = 0.5$?

Use the coordinate point ($0.5$, ______) to calculate a new slope and find the coordinate point at $x = 1$.
Do the same to find the coordinate at $x = 1.5$
And again at $x = 2$.

$(2, 1.5)$