Hey

Question:

Evaluate the following limit: $\displaystyle \lim_{x\to9} \ \frac {\sqrt{x} - 3}{9 - x} $

Solution:

I tried multiplying by the conjugate, but that gives me: $\displaystyle \frac {x - 9}{(9 - x)(\sqrt {x} + 3)} $

and I really don't know what to do from here. The top now gives 0, and I can't factor it out using the bottom. Help?