Corollary: Sum of Two Supplemental Angles Equals Two Right Angles
(related to Proposition: 1.13: Angles at Intersections of Straight Lines)
The sum of two supplemental angles equals two right angles.
Table of Contents
Proofs: 1
Mentioned in:
Proofs: 1
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References
Adapted from CC BYSA 3.0 Sources:
 Callahan, Daniel: "Euclidâ€™s 'Elements' Redux" 2014
Adapted from (Public Domain)
 Casey, John: "The First Six Books of the Elements of Euclid"