Proposition: Prop. 12.02: Areas of Circles are as Squares on Diameters
Euclid's Formulation
Circles are to one another as the squares on (their) diameters.
* Let $ABCD$ and $EFGH$ be circles, and [let] $BD$ and $FH$ [be] their diameters.
* I say that as circle $ABCD$ is to circle $EFGH$, so the square on $BD$ (is) to the square on $FH$.
Modern Formulation
(not yet contributed)
Table of Contents
Proofs: 1
 Lemma: Lem. 12.02: Areas of Circles are as Squares on Diameters
Mentioned in:
Proofs: 1 2 3
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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