Corollary: Angles of Right Triangle
(related to Proposition: 1.32: Sum Of Angles in a Triangle and Exterior Angle)
If one angle of a triangle equals the sum of the other two, then it is a right angle. In other words, if \(\beta=\alpha + \gamma\) then \(\beta=90^\circ\).
Table of Contents
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"