What would you say if...?

What would you say if (something were to happen)?

Used to gauge someone's reaction to some hypothetical future action, occurrence, or outcome. A: "Mom? What would you say if I told you I was thinking of dropping out?" B: "I would be absolutely livid." I know you had your heart set on going to Disneyworld this summer, but what would you say if we decided to go to Paris instead?
See also: if, say, what
Farlex Dictionary of Idioms.

What would you say if...?

an expression introducing a request for an opinion or a judgment. Bill: What would you say if I ate the last piece of cake? Bob: Go ahead. I don't care. Mary: What would you say if we left a little early? Sally: It's okay with me.
See also: say, what
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • What would you say if (something were to happen)?
  • pigs might fly
  • bonus
  • Bonus!
  • so help you (God)
  • you would think
  • maybees don't fly in June
  • might just as well
  • could just as well
  • could/might just as well...