Corollary: Triangulation of an Ngon and Sum of Interior Angles
(related to Proposition: 1.32: Sum Of Angles in a Triangle and Exterior Angle)
If a convex nsided figure is triangulated, the sum of its angles equals \(2(n2)\) right angles.
\[\sum \alpha_i=(n2)\times 180^\circ=2(n2)\times 90^\circ\]
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"