<Tri-2024-2154>, hint
Let line BE cut circumcircle of ACE in F.
Since triangles ECD and CBD are similar CD^2=DE x DB
Since AECF are cyclic, AD xDC=DF xDE=CD^2. Hence DB=DF DA=DC ABCF is a parallelogram
<CFB=<ABF. Let CH be the tangent to circle AEC (H on AB)
<ECH=<EFC=<ABF. ---> BCEH are concyclic <CEB=<CHB=90
No comments:
Post a Comment