Definition: Supplemental Angles
If a segment \(\overline{AC}\) stands on another segment \(\overline{DB}\), like shown in the following figure:
then the formed angles \(\angle{BAC}\) and \(\angle{CAD}\) are called supplemental.
Mentioned in:
Axioms: 1
Corollaries: 2 3 4
Proofs: 5
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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"