Page 250 - DK Children's Encyclopedia

Symmetry SEE ALSO

▸ ▸ Art p.28
▸ ▸ Flowers p.103
There are two types of symmetry. Reflective symmetry is ▸ ▸ Human body
when lines can be drawn to divide a shape into identical p.130
parts. Rotational symmetry is when a shape can be turned ▸ ▸ Shapes p.222

around (rotated) and still look the same. ▸ ▸ Sight p.226
▸ ▸ Games
pp.240–241

Reflective symmetry
Lines of symmetry are like folding a shape in half. If a A regular octagon
has eight lines of
shape is symmetrical, both sides of the fold will look the symmetry, through
same. Shapes can have more than one line of symmetry. its sides and angles.

This triangle has
three lines of
Diamonds have two symmetry, one
lines of symmetry. through each side.
Each one splits the
diamond into two
equal parts.

Diamond Equilateral triangle Octagon

Rotational symmetry A circle has
Symmetry in nature If a shape can be turned and a never-ending
Nature has many examples of both types of its outline looks the same, it number of lines
symmetry. Most animals, including humans, are has rotational symmetry. This
roughly the same on both sides—they have a line of rotational
of symmetry down the middle. sequence shows how a square symmetry.
Reflective Rotational has rotational symmetry.
symmetry symmetry Direction
of rotation

1 2 3 4
Leaf Starfish Point of rotation A square can turn within
its shape four times.
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