$\emptyset$, $inconsistent$, $parallel$.
Work Step by Step
In the case that we get $0=3$, this means that the system of equations are inconsistent and have no solutions. In other words, the solution set is an empty set $\emptyset$. The linear system is an $inconsistent$ system. For such systems, the graph of the lines will be $parallel$; that is, there are no intersections or solutions. To summarize, the answers to this question are: $\emptyset$, $inconsistent$, and $parallel$.