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.

1Angles 1 and 2 are supplementary. The definition of supplementary.
2Angles 2 and 3 are supplementary. The definition of supplementary angles.
3Angles 1 and 3 are congruent. Q.E.D. The Supplementary Angle Congruence Theorem
Table 1: Proof of the Vertical Angle Congruence Theorem


  1. McAdams, David E.. All Math Words Dictionary, vertical angles. 2nd Classroom edition 20150108-4799968. 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.

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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.)

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