## X(663) (CROSSDIFFERENCE OF X(2) AND X(7))

 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) = a(b - c)(b + c - a)
Barycentrics    g(a,b,c) : g(b,c,a) : g(c,a,b), where g(a,b,c) = af(a,b,c)

X(663) lies on these lines:
1,514    41,884    101,919    106,840    187,237    513,855    650,861    657,853    661,810

X(663) = reflection of X(649) in X(667)
X(663) = isogonal conjugate of X(664)
X(663) = X(I)-Ceva conjugate of X(J) for these (I,J): (101,41), (109,6)
X(663) = crosspoint of X(I) and X(J) for these (I,J): (1,101), (6,109)
X(663) = crosssum of X(I) and X(J) for these (I,J): (1,514), (2,522), (100,651), (521,1214), (693,1441)
X(663) = crossdifference of any two points on line X(2)X(7)

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