MOST of the time if there's any "PA" you will find a box of cords, mics, and at least one DI box(usually with a ground lift switch). If not, your line out will be fine. My BODXTL goes about 30 feet in a Monster Studio Link unbalanced into whatever I use(either QSC 2402's or BOSE PAS depending on venue).
As long as the snake cable has decent shielding you should be fine but be sure to:
Have the IDIOT switches on the back set correctly. Switch #1 as you normally set it, switch # 2 to LINE.
I've been bitten by these accidentally in the wrong position(s) and have resorted to checking them at every gig(see reminder arrows on my POD):
Set the software output to STUDIO DIRECT(see manual if needed).
Turn the volume "stub" on the back next to Idiot Switch #2 to wide open.
Run you mixer signal into a LINE LEVEL or AUX input on a channel.
Make SURE you patches' volumes have been leveled so you don't change from one to another and drop out of the mix or get suddenly louder.
NOTE:
If "they" let you use two lines, send one from the "DI" output and one from "MODEL" output.
If they only give you one, send the PA the "MODEL" output.
That should cover it.
