Problem B. 4798. (May 2016)
B. 4798. In a cyclic quadrilateral \(\displaystyle ABCD\), diagonals \(\displaystyle AC\) and \(\displaystyle BD\) are perpendicular, and the centre of the circumscribed circle is \(\displaystyle K\). Prove that the areas of triangles \(\displaystyle ABK\) and \(\displaystyle CDK\) are equal.
(4 pont)
Deadline expired on June 10, 2016.
Statistics:
104 students sent a solution.  
4 points:  101 students. 
3 points:  1 student. 
2 points:  1 student. 
0 point:  1 student. 
