Bb 9/F
The Bb 9 chord consists of the Bb (Perfect unison), D (Major third), F (Perfect fifth), Ab (Minor seventh) and C (Major ninth) notes, with F as the bass note.

How to play the Bb 9/F chord
- Play F as the lowest bass note in the left hand
- Find Bb (Root) on the piano keyboard
- Add D (Major third) — 4 semitones above Bb
- Add F (Perfect fifth) — 7 semitones above Bb
- Add Ab (Minor seventh) — 10 semitones above Bb
- Add C (Major ninth) — 14 semitones above Bb
- Press all 6 notes simultaneously to sound the Bb 9/F chord