how to find rule of rotation
Coordinate Rules for Rotations. In general, we can state the following coordinate rules for (counterclockwise) rotations about the origin: For a rotation of 90o: (x, y) --> (ây, x) For a rotation of 180o: (x, y) --> (âx, ây) For a rotation of 270o: (x, y) --> (y, âx)