Question

I’m not 100% how to do this

Answer 1

You can simply pick 3 random values for the independent variable, namely "x", lemme pick two, hmmmmmmm 2 and hmmmmmm -14, there, now, what's "y"?

$\bf \boxed{2}-3y=-7\implies -3y=-9\implies y=\cfrac{-9}{-3}\implies y=3\qquad \qquad \underline{(2,3)} \\\\\\ \boxed{-28}-3y=-7\implies -3y=21\implies y=\cfrac{21}{-3}\implies y=-7\\\\\\ \underline{(-28,-7)}$

and pick another random value for "x", get "y", and plot those three points.