Shalabh's Quants wrote:
Statement 2...
Imagine Rectangle. All angels are equal but one cannot have all 4 vertexes on a circle. Insuff.
C.
Agreed that statement 2 is insufficient.
However, a rectangle may not be the right example. Even a rectangle is a cyclic quadrilateral - i.e., a circle can always be drawn touching the 4 vertices of a rectangle.
Any quadrilateral whose opposite angles are supplementary is a cyclic quadrilateral (works vice versa also).
Statement 2 could be proved to be insufficient with a hexagon which looks like this ...
If a circle is drawn which passes through the 3 vertices on the left portion of the hexagon, then, the other 3 vertices will not lie on the circle. This is, in spite of, all the angles being equal.
I hope this helps. Thanks.
Naveenan Ramachandran
4GMAT, Dadar(W) & Ghatkopar(W), Mumbai