We have $y \propto x \Rightarrow y=m x$

Where $y$ denotes the force, $x$ denotes the acceleration and $m$ denotes the constant mass. Taking $m =6 \,kg$, we get $y =6 \,x$

Now, we form a table as follows by writing the value of $y$ below the corresponding value of $x$.

$\begin{array}{|l|l|l|l|} \hline X & 0 & 1 & 2 \\ \hline y & 0 & 6 & 12 \\ \hline \end{array}$

Plot the points $(0,0),(1,6)$ and $(2,12)$ on a graph paper and join any two points and obtain a line.