Probability question

I am having a really hard time figuring out what equations to use for what.

My problem is
A girl grabs 2 socks from a drawer with 9 black socks, 6 brown socks and 2 blue socks all mixed together.

What is the probability of her picking a pair of socks the same color?

What is the probability that the 1st sock pulled is brown?

\(\displaystyle \frac{\binom{9}{2}+\binom{6}{2}+\binom{2}{2}}{\binom{17}{2}}\)

Now you tell us why that is correct!