Bose - Surround Speakers 700 120-Watt Wireless Satellite Bookshelf Speakers (Pair) - White

I went to the Bose website and placed everything as they recommended the sub is in the front 1/3 of the room the rear speakers can be mounted to the wall, on a stand, to ceiling mounts, or on shelf mounts and need to be mounted behind you

Yes they are the same speakers.

Yes. The Surround Speakers 700 are compatible with the Soundbar 900.

For optimal playback, the speakers should be positioned nearby to the viewing location, at ear-level height. However, our ADAPTiQ calibration process can calibrate each individual speaker for optimal playback in the unique setting of your room.

It is not possible to add more than one pair of Surround Speakers to your set up. The maximum you can have is a Soundbar, single set of surround speakers and two of the same bass module