Online Geometry Problem 697: Square, Circle,
Area, Sector, Segment, Tangent, Inscribed, Congruence.
Level: High School, Honors Geometry, College,
Mathematics Education

The figure shows a square ABCD of area S and the inscribed circle of center O. Circles E and G are tangent to circle O and tangent each other at the center O. Prove that the area of the yellow shaded region is equal to three quarters of S.
See also:
Typography of problem 697 using mobile apps,
Problem 697 in motion.