Corollary: Existence of Parallel Straight Lines
(related to Proposition: 1.16: The Exterior Angle Is Greater Than Either of the Non-Adjacent Interior Angles)
If the segments \(\overline{BA}\) and \(\overline{CF}\) used to prove the proposition 1.16 were extended to straight lines \(BA\) and \(CF\), those straight lines could not meet at any finite distance. In other words, they are parallel.
![Fig5p5p19_1](https://github.com/bookofproofs/bookofproofs.github.io/blob/main/_sources/_assets/images/examples/Fig5p5p19_1.jpg?raw=true)
Table of Contents
Proofs: 1
Mentioned in:
Axioms: 1
Definitions: 2
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References
Adapted from CC BY-SA 3.0 Sources:
- Callahan, Daniel: "Euclid’s 'Elements' Redux" 2014
Adapted from (Public Domain)
- Casey, John: "The First Six Books of the Elements of Euclid"