CPhill already answered to the same one before here it is:
The points ( 2,0) and (0, -4) are on the line
Slope of line = (-4 - 0) / ( 0 -2) = -4/-2 = 2
Equation of line (using 0,-4) is
y= 2x -4
Since we have an solid line the inequality is either
y ≤ 2x - 4 or y ≥ 2x - 4
Note that (3,1) is in the yellow region
If we test this point in both inequalities, note that
1 ≤ 2(3) - 4
1 ≤ 6 - 4
1 ≤ 2 is true
So....the correct inequality is y ≤ 2x - 4
