Perpendicular Line Tool
From GeoGebra Manual
- Selecting a line (or a segment) and a point creates a straight line through that point perpendicular to the line (or segment).
- The line’s direction is equivalent to the perpendicular vector of the selected line or segment. (See also PerpendicularVector command).
- This tool has also a version applicable to 3D objects: Select point and perpendicular line or plane.
- See also PerpendicularLine command.