Bill...

The Yamaha EMX 212s is a powered mixer. You would want to go out of the main outs on the front to go to your Bose Compacts.

YOU DO NOT WANT TO SEND A POWERED SIGNAL TO THE POWERED BOSE COMPACTS. You may have 2 expensive "compact" door stops!

You might want to go with...
Tyros 2 --- L/R 1/4" TS Instrument Cables out to channel 5/6 of the EMX 212s
TC Helicon --- L/R 1/4" TS Instrument Cables out to channel 7/8 of the EMX 212s
EMX 212s Front Main Out L/R 1/4" TS Instrument Cables to 1/4" TS on the Bose
--- It looks like channel 1-2-3-4 are mono channels with no pan control

If you need to run a longer distance, you could hook up a stereo DI box... 1/4" TS Instrument Cables from the EMX 212s to the DI Box---XLR Outs to Bose XLR in... then it will be balanced.

Main Out on the front of the Yamaha EMX 212s (Page 23)
----------
MAIN OUT L and R jacks
These unbalanced phone output jacks feed out the main
stereo output. You would typically connect these jacks to
a power amp or powered speakers. The signal sent to
these jacks is adjusted by the MAIN section’s MASTER
knob and graphic equalizer.
----------

Here's a link to the PDF manual on the Yamaha...

http://www.yamahacommercialaudiosystems.com/downloads/manuals/mixers/emx/emx512sc_manual.pdf

Another idea is to invest in a smaller non-powered mixer.
Yamaha MG06x $119 - Balanced XLR Out... No EQ on the Stereo Channel
Yamaha MG10xu $199... http://www.sweetwater.com/store/detail/MG10XU/

Hope that helps and enjoy the compacts!!!