A bisector is a line which cuts another line exactly in half. An angle bisector cuts an angle into two angles of equal size. It can be constructed using a ruler and a pair of compasses.

An angle bisector cuts an angle into two angles of equal size. To construct an angle bisector, three arcs must be drawn. One from the corner of the angle and two smaller arcs from the points of ...

This is how you do it: Construct an angle, any angle. Bisect it. At a point, any point, on the line of bisection, draw lines to sides of angle and perpendicular to bisector.