To Create a Construction Line That Bisects an Angle (AutoCAD Mechanical Toolset)

1. Click Home tabConstruction panelConstruction LinesBi-sect. Find

1. Select the first, and then the second line of the angle, or press ENTER to define the angle.
2. Select the first, and then the second line of the angle.

Note:

To define the angle press ENTER, select the vertex of the angle, then select the first and the second endpoint of the vertex.