Short animation of geometry

I need a short (<8s) animation of a simple geometry theory called the Inscribe Angle Theorem - showing that the angles of triangles within a sphere stay the same. I've attached some still images below which I'd like to be similar to.

It would be great if the circle could be drawn, and then three triangles are drawn in the same place and then move around the circle (fixed at the base and moving at the point where the point of the triangle meets the circle) and move to the three positions, change colour at their new position and the angle which is the same is highlighted (as in attached axample 'images(1)'.

So in the example graph 'images' A and B stay fixed, F, B and G all move. In the example 'f-inscribed_angles', A and C are fixed, D/B/F would move. I hope this makes sense!



I need this asap so fast turnaround would be appreciated.