Segment Addition Postulate

Pronunciation: /ˈsɛg mənt əˈdɪ ʃən pɒs tʃə leɪt/ ?

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Manipulative 1: Segment addition postulate. Click on the green points and drag them to change the figure.

The segment addition postulate states that given three points A, B and C on a line, C is between A and B if and only if AC + CB = AB. If C lies between A and B, then the sum of AC and AB equals AB. Also, if the sum of AC and AB equals AB, then C lies between A and B.

This postulate defines what it means to say "Point C is between point A and point B." If point C is not on the same line as AB, then the distance of AC plus CB is always greater than AB. So, a point can not be between two other points unless it is on the same line as the other points. If C is on the same line as A and B, but lies outside of A and B, then AC + CB > AB.

More Information

  • McAdams, David E.. Between. allmathwords.org. All Math Words Encyclopedia. Life is a Story Problem LLC. 2010-03-16. http://www.allmathwords.org/article.aspx?lang=en&id=Between.

Cite this article as:


Segment Addition Postulate. 2010-03-15. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/s/segmentadditionpostulate.html.

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2010-03-16: Authored (McAdams, David.)

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