X(4), X(5), X(3146)
vertices of the pedal triangle of the reflection of X(2883) in X(4)
Ix-anticevian points : see table 23
Its asymptotes are parallel to the altitudes and concur at X(3627) = reflection of X(5) in X(4).
It is the locus of point P such that the reflection triangle of ABC in the sidelines of ABC and the pedal triangle of P are perspective. See also Table 6.
The locus of the perspector is K117 = C(3).