Interactive Applet |
You can move the points A, B and C (click on the point and drag it).
Press the keys “+” and “−” to zoom in or zoom out the visualization window and use the arrow keys to translate it.
You can also construct all centers related with this one (as described in ETC) using the “Run Macro Tool”. To do this, click on the icon , select the center name from the list and, then, click on the vertices A, B and C successively.
Information from Kimberling's Encyclopedia of Triangle Centers |
Trilinears cos A sec 2A : cos B sec 2B : cos C sec 2C
Barycentrics tan 2A : tan 2B : tan 2CLet A'B'C' be the reflection of the orthic triangle of ABC in X(5). The lines AA', BB', CC' concur in X(68), as proved in
V. V. Prasolov, Zadachi po planimetrii, Moscow, 4th edition, 2001.
Coordinates for X(68) can be obtained easily from the Ceva ratios given his Prasolov's proof of concurrence.
X(68) lies on these lines:
2,54 3,343 4,52 5,6 11,1069 20,74 26,161 30,64 65,91 66,511 73,1060 136,254 290,315 568,973X(68) = reflection of X(155) in X(5)
X(68) = isogonal conjugate of X(24)
X(68) = isotomic conjugate of X(317)
X(68) = anticomplement of X(1147)
X(68) = X(96)-Ceva conjugate of X(3)
X(68) = cevapoint of X(I) and X(J) for these (I,J): (6,161), (125,520)
X(68) = X(115)-cross conjugate of X(525)