Explanation:
You need to divide both sides by 3 to get x by itself:
x > -4
<-l-------l-------l-------l-------l--------l--------l--------l-------l->
4 3 2 1 0 1 2 3 4
You would place your point on -4, but it's opened because there is not an equal to sign underneath the inequality symbol. The "<" is pointing to the right so you would shade the number line on the right following -4.