A shape has line symmetry (or reflective symmetry) when you can fold it along a line and both halves match exactly. That fold line is called the axis of symmetry or mirror line.
A shape has rotational symmetry when it looks the same after being rotated by less than a full turn. A square looks identical after 90°, 180°, and 270° rotations.
A shape can have one type of symmetry, both, or neither. A scalene triangle has neither. An equilateral triangle has 3 lines of symmetry and rotational symmetry of order 3.
Remember
Lines of symmetry = fold lines. Rotational symmetry = how many times it looks the same in one full spin.
Real World
Butterflies, faces, and leaves often have line symmetry. Snowflakes typically have 6-fold rotational symmetry — they look the same every 60°.
Feeling ready?
Put this concept to work with a practice workout.