Quote:
Originally Posted by ewmayer
Assume the initial circle is centered at (0,0) and has radius 1. Now draw a pair of circles of half that radius, one centered at (0, 1/2), the other at (1/2, 0). These intersect (in the sense of touching at a single point) at (0,0), and thus subdivide the large circle into 4 equalarea subsets, two of which are circles, two of which are not.

I would claim that this is a "radial" solution since it has point symmetry about the origin.