##  [Angle Bisector Theorem](/angle-bisector-theorem) 

  ##  [Angle Bisector Theorem](https://puremath.quantumdictionary.io/angle-bisector-theorem-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A triangle theorem stating that an internal angle bisector from vertex A meeting side BC divides BC into segments proportional to the adjacent side lengths: if the bisector meets BC at D then BD/DC = AB/AC.