Geometry APP lines

[Tonig00]

Hello

In Geometry APP, it seems that the line() function behaves oddly when defined with two points:
The points in the line() function should be introduced as a complex number (the green line in the attachment is correct). If you introduce it as a vector then the line (blue) is drawn perpendicular to the former one.

This can be circumvented as described (i.e. using complex numbers rather than vectors) in 2 dimensions, but this is not possible in 3 dim.
Is there any way to solve this?
Following this issue, is there some way to draw lines (from two points) in Graph 3d APP? Similar to line() function? Will it be geometry in 3D?

Thanks for your comments

Toni