Let $f$:$R^{2}R$ and suppose that $\underset{(x,y)(3,0)}{lim}f(x,y)=-10.$ What can you say about the value $f(3,0)?f$ may or may not be continuous at $(3,0).$ Nothing can be said about the value $f(3,0).f(3,0)=-10f$ is continuous at $(3,0).f(3,0)-10$