y = 3x + 1
is a linear equation, a straight line ("line-ar means "line")
It's in slope intercept form, where the constant term = the y intercept 1 = the point (0,1)
coefficient of the x term = the slope = 3
easiest way to graph it is find a 2nd point such as (x,y) = (3, 10) Then plot (3,10) and (0,1), and connect them with a straight line.
then put arrows at the ends of the line to indicate the line goes forever in both directions