Two Questions

Hello Again….two questions…sorry for for repeating an old one:

1) Which were the dominant choices that were “married?” I seem to remember b9 only goes with one as well as the 9 only goes with one?

2) I seem to remember that Suds suggested an option to plying a dominant voicing. Is this the option: On the L hand, play the Root and b7, and on the right hand, play a major chord in any inversion a whole step higher than the root of the chord?
EXAMPLE: Lets say I’m voicing a “C” note associated with a C7 chord.
On the left hand, can I play play C and Bb / and with the Right hand play D, F#, A, and C?

Thank you
– Angelo