Proposition: Prop. 9.02: Numbers whose Product is Square are Similar Plane Numbers
Euclid's Formulation
If two numbers make a square (number by) multiplying one another then they are similar plane numbers.
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