Hi guys, I'm working through a bunch of problems in which I have to determine the type of indeterminate form (i.e. infin/infin, 0/0). This one is throwing me for a loop though:

$\displaystyle $\underset{x\to -{3}^{-}}{lim}\left(\frac{x}{{x}^{2}+2x-3}-\frac{4}{x+3}\right)$$

When I substitute in the -3, I get 3/0 - 4/0, but I obviously can't divide by 0. What is the indeterminate form in this case?