When Springfield legalized gambling, Robert Goulet guest starred as himself, set to perform at Mr. Burns' casino until Bart tricks him into performing at his tree house.
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The Simpsons Season 5 Episode 10 Quotes

Homer: (Wearing glasses) The sum of the square roots of any two sides of an isosceles triangle is equal to the square root of the remaining side!
Man: (From inside a bathroom stall.) That's a right triangle, you idiot!
Homer: D'oh!

(to Marge) You promised Lisa to help her with her costume. You made her cry. Then I cried. Then Maggie laughed...she's such a little trooper!

Homer