Embarrassingly n00bish question about the 3X outs

[Barnelby]

Ok guys please know it takes me a lot of courage to reveal this kind of naivete about my TI2 after owning it for about 8 months....

I got a new set of monitors, and just to satisfy my boyhood desires for the ultimately loud setup (temporarily) I would like to play though my old rokits +rokit sub and my new yamaha hs80ms. Suicidal, I know. But I'm just in the kind of mood where I want to move the house off the foundation.

So I am running quarter inchers from the 1 and 2 outs, but only out 1 is working.

So I guess my first question is: How do I make multiple outputs work simultaneously?

And what exactly am I supposed to do with three if I needed them? I see people complain sometimes about there only being three and I'm like wtf why would you need more than one?

Like i said, n00b to the max, no trying to deny it. I googled it first to try and avoid asking but alas.