On And Off
The line is the Perpendicular Bisector of segment AB
Green point C is ON the perpendicular bisector line.
Orange point D is OFF the perpendicular bisector line.
Drag and Observe:
> Move point C along the perpendicular bisector
> Move point D around in space
> Move point D onto the perpendicular bisector, then off again
> Move either endpoint of segment AB
How do the distances change as the points move?