You can bisect the angle between any combination of line types; line, segment, vector, or polygon side with these steps:
| 1. | Select  two of any of the line types listed above. |
| 2. | Click the Angle Bisector tool  or select Angle Bisector from the Construct menu. |
An infinite line will appear between the two selected lines. You can use the Calculate / Angle tool to get the value of the bisected angle.