Euclid:Proposition/XI/9

Proposition

In the words of Euclid:

Straight lines which are parallel to the same straight line and are not in the same plane with it are also parallel to one another.

(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