Let S Be a Square
The proof phrase 'let S be a square' is played as a royal command that a parallelogram must obey.
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Free for classrooms, worksheets, slides and other non-commercial use under CC BY-NC 4.0, with credit to Ben Orlin.
Cartoon by Ben Orlin, Math with Bad Drawings. https://cartoons.mathwithbaddrawings.com/2019-03-26-let-s-be-a-square/ (CC BY-NC 4.0)Transcript
A: "Let S be a square." S: "Thanks, but I'd rather be a parallelogram."
A (stern): "I said, let S be a SQUARE." S (now a square): "Yes, your Grace."