Proposition: Prop. 10.070: Straight Line Commensurable with Side of Sum of two Medial Areas
(Proposition 70 from Book 10 of Euclid's “Elements”)
A (straight line) commensurable (in length) with the square root of (the sum of) two medial (areas) is (itself also) the square root of (the sum of) two medial (areas).
Modern Formulation
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Table of Contents
Proofs: 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