Euclid:Proposition/XI/6

Proposition

In the words of Euclid:

If two straight lines be at right angles to the same plane, the straight lines will be parallel.

(The Elements: Book $\text{XI}$: )


Sources

  • 1926: Sir Thomas L. Heath: Euclid: The Thirteen Books of The Elements: Volume 3 (2nd ed.) ... (previous) ... (next): Book $\text{XI}$. Propositions
This article is issued from ProofWiki. The text is available under Creative Commons Attribution-ShareAlike License unless otherwise noted. Additional terms may apply for the media files.