r2070

Let La, Lb, Lc be three parallel lines going through A, B, C; Ma, Mb, Mc their perpendiculars from A, B, C. Let Pab be the intersection between La and Mb, and define cyclically Pba, Pbc, Pcb, Pca, Pac. The lines PabPba, PbcPcb, PcaPac concur at a point in the ninecircle.


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