Reply to 2nd Gig

Ok, So Yesterday was my first gig, and it went great. I played on a Bose surround sound system at my friends house (yeah, I know...), but everything went great!

Anyway I have a 2nd gig coming up and It will be at an actual venue, and i managed to borrow a pair of 15 inch Passive JBL's. (I don't know what model)

Now, I never used a PA system before, so I don't exactly know what to use to run a successful gig.
I was told I need a mixer (http://www.musiciansfriend.com/pro-a...k-ub1202-mixer)
to connect to my Numark 4Trak, and then connect to the Speakers?
Is this true? Would I also need an Amplifier?

I'm so lost...

I would believe that I could just run XLR cables from the back of my 4Trak directly into the speakers.

So do I need an Amplifier? A Mixer? and what cables?

Thanks!

- Nitrotix