Interoperable interactive geometry for Europe
I forgot my login data

Report a bug

Fan club

Quick Intro Videos
click to start movie
Create A Simple
GeoGebra Resource (25Mb)
click to start movie
Filing a review
click to start movie
Find a Resource

This platform is brought to you by the intergeo project, funded under the eContent Plus programme of the European commission and by partners


Returns the two lines which are bisectors of two given lines. That is, line_angular_bisectors_of_two_lines(b1,b2,l1,l2) states that b1 and b2 are the bisectors of l1 and l2. Both arguments l1 and l2 can be of any type within the line_family.

Pathological cases:

  • If the two bisected lines are parallel, behaviour is undefined.
  • If the two bisected lines are coincident, the first returned bisector must be same line, and the behaviour of the second is undefined.


  1. line through two points example: source JSXGraph