How do the measures of the angles of ABC compare with those of A'BC'when A'B'C coinddes wth the other three triangles? What can you say about the presenvation of the angle measurements of a shape during a rotation?
The measure of each angle of abc is equal to the corresponding angle of a'b'c' when coincides with the other three triangles. The measures of the angles of the triangle are preserved as the figure rotates.
