The figure below shows a circle O with
radius OB perpendicular to radius OA. CD is perpendicular to OA (C on
circle O, D on OA). OC and BD extended meet at E. Circle of radius OE
meets OA extended at F. EG is perpendicular to OF (G on OF). Prove that
AF = EG.

Art of Geometry Problem 985 using Mobile Apps. Circle Patterns.
Geometric art is a form of art
based on the use and application of geometric figures. A
geometric figure is any set or combination of points,
lines, surfaces and solids. A mobile app or mobile
application software is a computer program designed to run
on smartphones and tablet computers.