Vertical Angles
Pronunciation: /ˈvɜr.tɪ.kəl ˈæŋ.gəlz/ Explain
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 Manipulative 1  Vertical Angles Created with GeoGebra. 
 Manipulative 1: Vertical angles. 

Vertical angles are a pair of
angles
formed by
intersecting
lines that are opposite each
other. Each pair of intersecting lines forms four angles and two pair of
vertical angles.
Vertical Angle Congruence Theorem
The Vertical Angle Congruence Theorem shows
that vertical angles are always congruent.
Step  Description  Justification 
1  Angles 1 and 2 are supplementary. 
The definition of supplementary. 
2  Angles 2 and 3 are supplementary. 
The definition of supplementary angles. 
3  Angles 1 and 3 are congruent. Q.E.D. 
The Supplementary Angle Congruence Theorem 
Table 1: Proof of the Vertical Angle
Congruence Theorem 

References
 McAdams, David E.. All Math Words Dictionary, vertical angles. 2nd Classroom edition 201501084799968. pg 189. Life is a Story Problem LLC. January 8, 2015. Buy the book
Cite this article as:
McAdams, David E. Vertical Angles. 12/21/2018. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/v/verticalangles.html.
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Revision History
12/21/2018: Reviewed and corrected IPA pronunication. (
McAdams, David E.)
12/17/2018: Removed broken links, updated license, implemented new markup. (
McAdams, David E.)
8/7/2018: Changed vocabulary links to WORDLINK format. (
McAdams, David E.)
5/5/2011: Initial version. (
McAdams, David E.)