0

The quadrilateral ABCD is inscribed in a circle with center O. Connect AC and BD intersecting at K.O1 is the circumcenter of triangle ABK and O2 is the circumcenter of triangle CDK. A line l through K intersect the two circumcircles at E and F respectively, and the circumcircle of ABCD at G and point H. Prove that EG = FH.

http://imc-official.chiuchang.org/files/2017imc/2017InIMC_Keystage_III_Team_ENG.pdf

IWYMIC Team Contest 2017 problem 6

THANK

user766994
  • 9
  • What have you tried? Where are you stuck? – Calvin Lin Apr 02 '20 at 18:46
  • No correlation found – user766994 Apr 02 '20 at 18:52
  • Please note that this site has a strong community, and posts are welcome when they fulfill some criteria, designed to make it stronger. Support for the question in form of figures (for geometry problems), origin, level, expected kind of solution, first own steps on the road and the first point of getting stuck, motivation, etc. should be present. In this case we have a stand alone, isolated question, not far away from a copy+paste. This "attracts" down-votes for the post and is frustrating for both, poster and readers. Please add details to not distroy a potentially interesting question. – dan_fulea Apr 03 '20 at 10:42

0 Answers0