It makes us think there is new information or a follow-up question and we spend time opening the thread. Simply click on the Thank button at the bottom left-hand corner of any post you find helpful. I agree with Mike.
Symmetry comes from a Greek word meaning 'to measure together' and is widely used in the study of geometry. Mathematically, symmetry means that one shape becomes exactly like another when you move it in some way: turn, flip or slide.
1 The mathematical term for identical shapes is congruent - in mathematics, identical means they are the same tile. 2  The tiles are usually required to be homeomorphic (topologically equivalent) to a closed disk, which means bizarre shapes with holes, dangling line segments or infinite areas are excluded.