Which type of symmetry is displayed?

Answer 1

"Displayed" is not a type of symmetry.

There are two types of symmetry:

• Reflectional (or mirror) in which a line can be placed on a shape in such a way that if the shape was folded along that line the two halves would match exactly. For example the letter W has a line of symmetry that runs vertically down its middle which allows the two halves to be folded onto each other to form a single V. The line is like placing a mirror on the shape.
• Rotational symmetry in which a shape is rotated about some point and fits back onto its initial position; in this case, the rotational symmetry is the number of times the shape fits onto its initial position when turning around 360°. When I was at school every shape had a rotational symmetry of at least 1 as the shape must fit back onto itself once it has turned 360°, however now it appears that it has changed so that if a shape only fits onto itself after a complete rotation it has no rotational symmetry, or a rotational symmetry of 0, but if it fits more than once, then the final fit counts, eg a rectangle has a rotational symmetry of 2 as it fits back onto itself after 180° and 360°.