Proposition: Prop. 11.16: Common Sections of Parallel Planes with other Plane are Parallel
Euclid's Formulation
If two parallel planes are cut by some plane then their common sections are parallel.
* For let the two parallel planes $AB$ and $CD$ have been cut by the plane $EFGH$.
* And let $EF$ and $GH$ be their common sections.
* I say that $EF$ is parallel to $GH$.
Modern Formulation
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Table of Contents
Proofs: 1
Mentioned in:
Proofs: 1 2
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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