Problem B. 4779. (March 2016)
B. 4779. The two points dividing side \(\displaystyle AB\) of triangle \(\displaystyle ABC\) into three equal parts, and the two points dividing side \(\displaystyle BC\) in a 1 to 3 ratio form a cyclic quadrilateral. The circumscribed circle of the quadrilateral is tangent to side \(\displaystyle CA\). Determine the angles of triangle \(\displaystyle ABC\).
(4 pont)
Deadline expired on April 11, 2016.
Statistics:
79 students sent a solution.  
4 points:  61 students. 
3 points:  8 students. 
2 points:  4 students. 
1 point:  3 students. 
0 point:  2 students. 
Unfair, not evaluated:  1 solution. 
