Category: Points defined for a triangle

In geometry, the orthopole of a system consisting of a triangle ABC and a line ℓ in the same plane is a point determined as follows. Let A ′, B ′, C ′ be the feet of perpendiculars dropped on ℓ from A
Brocard points
In geometry, Brocard points are special points within a triangle. They are named after Henri Brocard (1845–1922), a French mathematician.