$\displaystyle -(\frac{\sqrt{3}}{6}) - (2*\frac{\sqrt{3}}{6})$ BAD...

Actually, I think I mistyped it into the forum. [edit] Even though I mistyped it, I think it is still the same.

I'm not sure where I'm going wrong with it. Is there a 'radical tutorial' website that'll be helpful?[/edit]

$\displaystyle -(\frac{\sqrt{3}}{6}) - (\frac{2\sqrt{3}}{6})$

$\displaystyle -(\frac{\sqrt{3}}{6})$

I know the denominator should eventually be a 2, but I just do see that happening at any time of simplifying the solution.