Answer
\begin{array}{|c|c|c|c|c|c|} \hline x & {-4} & {-2} & {0} & {2} & {4} & {8} \\ \hline y & {2} & {0} & {4} & {4} & {6} & {8} \\ \hline \frac{d y }{ d x} & {6} & {2} & {4} & {2} & {2} & {0} \\ \\ \hline \end{array}
Work Step by Step
Given$$\dfrac{dy}{dx}=y-x$$ and
\begin{array}{|c|c|c|c|c|c|}\hline x & {-4} & {-2} & {0} & {2} & {4} & {8} \\ \hline y & {2} & {0} & {4} & {4} & {6} & {8} \\ \hline \dfrac{d y }{d x } & { } & { } & { } & { } & { } & { } \\ \hline\end{array}
$$$$
Since the $1^{st}$ derivative $(\dfrac{dy}{dx}) $ mean the slope, so by substituting by the values of points we get,
\begin{array}{|c|c|c|c|c|c|} \hline x & {-4} & {-2} & {0} & {2} & {4} & {8} \\ \hline y & {2} & {0} & {4} & {4} & {6} & {8} \\ \hline \frac{d y }{ d x} & {6} & {2} & {4} & {2} & {2} & {0} \\ \\ \hline \end{array}
