We have the following function:

First, We leave the function in the form of the equation of the line y=mx+b.

Now we pick two random points to replace in the function.
We use x=-2 and x=1 remember, these points can be anything, not necessarily these.
Now we solve x=-2 and x=1


The points are:

Second, with these points, we draw a line between these two points, so we can describe the line of the line function.