Red: So, you're allegedly tutoring Kelso in math.
Eric: Yes, sir.
Kitty: Are you good in math?
Red: What's the square root of "x"?
Eric: Um, I really can't answer that.
Red: Aha!
Eric: No. See, "x" is a variable, so until you define its parameters the only possible answer is a variable, or "x" if you prefer.
Red: Is that right?
Kitty: Sounds good. Will Michael's parents be home?
Eric: Yes.
Kitty: Are they as dumb as he is?
Eric: I can't lie. Yes. Yes, they are.
Red: Right answer. That was a trick question. I know they're dumb.
Eric: So, I can go?
Red: You can go, but I'll be watching the news. And if anything is vandalized or explodes or catches on fire, "x" is gonna equal me kicking your ass.