Angle Bisector – Definition -Examples  The angle(interior) bisector of an angle is a line or line segment that divides the angle into two (congruent)equal parts.  The angle bisector is also called the internal angle bisector. In ∠ABC, BD is angle bisector of ∠ABC. In above figure BD is bisect the ∠ABC. ∵ ∠ABC = 900∴ ∠ABD   = 450and ∠DBC = 450 ∠ABD and ∠DBC […]