## X(119) (FEUERBACH ANTIPODE)

 Interactive Applet

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This applet was built with the free and multiplatform dynamic geometry software C.a.R..

 Information from Kimberling's Encyclopedia of Triangle Centers

Trilinears           f(A,B,C) : f(B,C,A) : f(C,A,B), where
f(A,B,C) = (csc A)(-1 + cos B + cos C)[sin 2B + sin 2C + 2(-1 + cos A)(sin B + sin C)]

Barycentrics    g(A,B,C) : g(B,C,A) : g(C,A,B) where
g(A,B,C) = (-1 + cos B + cos C)[sin 2B + sin 2C + 2(-1 + cos A)(sin B + sin C)]

X(119) = nine-point-circle-antipode of X(11)
X(119) = X(104)-of-medial triangle.

X(119) lies on these lines:
1,5    2,104    3,123    4,100    10,124    116,142    125,442    135,431    136,429    214,515    381,528    517,908

X(119) = midpoint of X(I) and X(J) for these (I,J): (4,100), (104,153)
X(119) = reflection of X(11) in X(5)
X(119) = complement of X(104)
X(119) = complementary conjugate of X(517)
X(119) = X(4)-Ceva conjugate of X(517)

This is a joint work of
Humberto José Bortolossi, Lis Ingrid Roque Lopes Custódio and Suely Machado Meireles Dias.