That depends of so many factors that I can not mention all:
1) How many players are in the pot?
BTN: Raises
SB: Re-Raises
BB: YOU
(NO INFORMATION ABOUT THE PLAYERS)
Discart to the flush
(BTN AND SB ARE AGRESSIVE PLAYERS)
Discart to the trips+ if you know the villain's hand range
(BTN AND SB ARE BOTH VERY THIGH PLAYERS)
Fold the Hand
---
BTN: Raises
SB: Folds
BB: YOU
(NO INFORMATION ABOUT THE PLAYER)
Re-raise and Discart One. Raise after the Discart
(BTN IS AGRESSIVE PLAYERS)
Discart to the trips+ if you know the villain's hand range
(BTN IS A THIGH PLAYER)
Call and change 3 and see how many cards did he Discart
---
BTN: Folds
SB: Raises
BB: YOU
(NO INFORMATION ABOUT THE PLAYER)
Re-raise and Discart 3
(SB IS AGRESSIVE PLAYERS)
Re-raise and Discart 3
(SB IS A THIGH PLAYER)
Call and Discart 3
OTHER FACTOR
2) How the table is playing (Aggressively or Passively)?
3) From what position did the raise come? What information do you have about that player who raise? What kind of player paid or Re-raises?
4) Do you think that after the discart the check-raise strategy will run successfully if you just change one and get the flush?
5) What kind of kickers do you have? 9-6-2 are very low kickers!