Page 224 - DK Children's Encyclopedia

Shapes SEE ALSO

▸ ▸ Constellations
p.73

Shapes are areas with different outlines. In math, there ▸ ▸ Flags p.102
are two types of shape. Two-dimensional shapes have ▸ ▸ Maps p.155
length and width, while three-dimensional shapes have ▸ ▸ Numbers p.185

length, width, and height. Shapes can be made of straight ▸ ▸ Symmetry p.248
or curved lines, or a mixture such as in a semicircle. ▸ ▸ Volume p.269

What makes a shape?
A shape is named depending on the number Line
of sides and angles it has. Regular shapes Edge A straight line is the
The side of a shape
have sides that are all the same length. is called an edge. shortest distance
between two points.
Angle Point
An angle is the A point is a place
place where two on a shape. It is
lines meet. shown with a dot.

Triangles have three sides and Circles have one long, round side. Squares have four equal sides and
three inside angles adding up to 180°. four right angles.

Angles
Angles are measured in degrees (º) out Polygons
of 360. Angles have different names “Polygon” is the name
depending on how big they are. for any flat, two-
dimensional shape.
Acute angle Right angle
An angle less An angle of
than a right exactly 90º.
angle (90º).
45° 90°

Obtuse angle 240°
An angle
between 90º Reflex angle
and 180º. An angle between
180º and 360º.

135°
Pentagons have five equal sides
and five inside angles.
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