Rotational Symmetry. How To Work Out The Order Of Rotational Symmetry Of A Shape.

Rotational symmetry is the amount of times a shape can be rotated onto itself in a full turn. The amount of times is referred to as the order of rotational symmetry. All shapes have at least order 1 rotational symmetry. However, if the order is 1 then the shape doesn't have rotational symmetry.
In example 1, you need to find the order of rotational symmetry of a parallelogram. The order of rotational symmetry of a parallelogram is 2 as the shape fits onto itself 2 times in a full turn.
In example 2, you need to find the order of rotational symmetry of an arrowhead. The order of rotational symmetry of an arrowhead is 1 as the shape fits onto itself only once in a full turn. Therefore it has no rotational symmetry.
In example 3, you need to find the order of rotational symmetry of an equilateral triangle. The order of rotational symmetry of an equilateral triangle is 3 as the shape fits onto itself 3 times in a full turn.