## Σάββατο, 1 Σεπτεμβρίου 2018

### 1985 BMO Shortlist 2 (GRE)

proposed by Dimitris Kontogiannis, Greece
[solved, alternate solutions are welcome]

Let ABC be a triangle with < A =120ο.  Let AD, CE be the angle bisectors of angles < Α, < C  respectively and I be the intersection point of AD, CE. If Z is the intersection point of BI and DE, calculate angle < DΑZ  .