​ Which graph represents the inequality?

Which graph represents the inequality?

Since we have a "<"  sign, the graph will have a dashed line....thus....only the top graphs are possible

Pick   (0,0)  and put it into the inequality....if it makes the inequality true, then the solution area will contain this point

18(0)  - 3(0)  <  -21

0  <  - 21

This is not true, so (0,0) isn't in the solution area....so......the top left graph is correct