Recent Additions

Problem 569: Quadrilateral, Excircles, Tangency Points, Congruence
The figure shows a quadrilateral ABCD with the excircle E tangent to AB at F, excircle G tangent to BC at H, excircle J tangent to CD at K, and excircle L tangent to AD at M, EF and GH meet at N, GH and JK meet at P, JK and LM meet at Q, and LM and EF meet at R. Prove that NP + QR = NR + PQ
