7. Opposite Angles of a Cyclic Quadrilateral

A cyclic quadrilateral has all 4 vertices (corners) on the circle.
7. Opposite Angles of a Cyclic Quadrilateral
Move the Points A,B,C and D to various positions on the circumference of the circle.[br][br]What do you notice about opposite angles in a cyclic quadrilateral?

Information: 7. Opposite Angles of a Cyclic Quadrilateral