The inequality is
.
Apply distributive property :
in the middle part.


Add 6 to each part.
\

Divide each part by 3.
\
Cancel common terms.
\
.
Graph the solution set for each inequality and find their intersection.
Observe the graph, the open circle means that
is not a solution of the inequality and the closed circle means that 5 is a solution of the inequality.
The solution set is
and its graph is