Points being the ninecenter of their pedal triangle
1) Let D be the foot of the A-altitude.
Take Db, Dc on BC such that BDb/BD = CDc/CD = -2.
2) The parallel from B to ADb cuts
AC at E.
3) The parallel from C to ADc cuts
AB at F.
4) The bisectors of BAC cut BC at
K, L.
5) Let Ha be the hyperbola {AKLEF}.
Define analogously Hb, Hc.
6) The three hyperbolas intersect
at the four possible positions of the requested point.
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