Angle Constraint

Any two of lines, segments, vectors or polygon sides can be constrained with an angle value or variable name with these steps:

1. Select   two from the line types listed above.
2. Click the Angle icon   .
3. Enter the constraint, real or symbolic. If you enter a real value, the lines will be adjusted to reflect the constraint.

Which Side to Constrain?

Sometimes when identifying angles, the constraint falls on the wrong one.  In the example below, we wanted BDC, not BDA.  Just click the cursor over the constraint arrow and drag it to the other side, then release the mouse button - done!

 

To get the reflex angle, hold the Ctrl key while dragging the angle symbol.

 

Note: The angular units are displayed in the lower right of the screen. You can choose Radians or Degrees in this window, or set the default Angle Mode in the Edit / Preferences / Math Properties menu, Math settings group.