Explanation:
first, we define the line.
the slope is -3 (as for every increase of x by 1 unit, y changes by -3 units, which makes the slope -3/1 = -3).
the y-intercept is 2.
so, the line is
y = -3x + 2
now the graph shows that we need to define all y values that are below (and that means smaller than) the result values of the line function.
the line is not included.
therefore the inequality is
y < -3x + 2 or 3x + y < 2