Angle Bisector
An angle bisector is a line or ray that divides an angle into two congruent angles.
Example :
Since 
is an angle bisector,
Therefore,
By the Angle Addition Postulate,
Substitute.
An angle bisector is a line or ray that divides an angle into two congruent angles.
Example :
Since is an angle bisector,
Therefore,
By the Angle Addition Postulate,
Substitute.