Proposition: 4.09: Circumscribing Circle about Square
(Proposition 9 from Book 4 of Euclid's “Elements”)
To circumscribe a circle about a given square.
* Let $ABCD$ be the given square.
* So it is required to circumscribe a circle about square $ABCD$.
Modern Formulation
It is possible to circumscribe a circle about a given square.
Table of Contents
Proofs: 1
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Sections: 1
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References
Adapted from (subject to copyright, with kind permission)
 Fitzpatrick, Richard: Euclid's "Elements of Geometry"
Adapted from CC BYSA 3.0 Sources:
 Prime.mover and others: "Pr∞fWiki", https://proofwiki.org/wiki/Main_Page, 2016