Cyclic Quadrilateral: Proof Hint

In the applet below, feel free to move the LARGE POINTS anywhere you'd like AT ANY TIME. Be sure to change the location of the BLUE POINT, PINK POINT, & other LARGE POINTS each time before you re-slide the slider. After interacting with this applet for a few minutes, please answer the questions that follow.


What is the SUM of the measures of the PINK ARC and BLUE ARC (that you see at the end of the animation)? Why is this?


What is the sum of the measures of the pink angle and blue angle? How do you know this to be true?

Quick (Silent) Demo