Perpendicular to a Segment Through a Collinear Point
1. Create a circle with a center at C that intersects segment AB at 2 different points (Not A or B).
2. Name those intersection points D and E.
3. Create a circle with a center at D that goes through E.
4. Create a circle with a center at E that goes through D.
5. Create point F at the intersection above segment AB.
6. Create line CF.
Line CF is perpendicular to segment AB.