Faisal and His Playgrounds

Faisal is a famous ice hockey player. He plays his game all across the world. But his favorite ground is Nirpur’s Yellow Cat Stadium. Whenever he plays at this ground, he performs. The Yellow Cat Stadium can be considered as a big circle. The ground is a quadrangle inscribed inside the circle, where the four vertices of the ground lies at the circumference of the stadium. Figure 1: Yellow Cat Stadium.

This is a companion discussion topic for the original entry at https://toph.co/p/faisal-and-his-playgrounds

Can anyone give me the link to the Editorial of this problem?