Head First 2D Geometry

Side lengths

can be dif

ferent.

All these angles

Sides ar

e

l

T

his isn’t just

true f

or r

egular

six-sided

p

olygons.

T

his is true for

regular p

olygons

wi

th an

y number

of sides.

equal sides and angles

Perimeter

Volume

Internal angles

C

ar

p

enter

s w

ant these angles.

If you put ar

ea her

e

that’s cool, t

oo! Y

ou’ll

see why in a bi

t.

What properties of the hot tubs do you need to work out to satisfy:

1. The bands?

2. The environment engineer?

3. The carpenters?

How does it help you that the tubs are all regular polygons?

Since all the sides on a regular polygon are the same length, then all the angles are equal

too, so we’ve only got to find one side and one angle—all the others will match.

People sit around the edges.

Regular polygons have equal sides and angles

Any six-sided polygon could have six different side lengths and

six different angles. But fortunately for us, all the hot tubs are

regular polygons. A six-sided regular polygon has six sides of

equal length and six equal angles.

REGULAR six-

Six-sided polygon:

sided polygon:

ar

e equal.

Sides a

ll equa

length, t

oo.

var

ious lengths.

All these angles

276 Chapter 7