## Is that a Polygon?

Polygons room 2-dimensional shapes. They room made of directly lines, and also the shape is "closed" (all the lines affix up).

 Polygon(straight sides) Not a Polygon(has a curve) Not a Polygon(open, no closed)

## Types of Polygons

### Regular or Irregular

A regular polygon has all angle equal and all political parties equal, otherwise it is irregular

 Regular Irregular

### Concave or Convex

A convex polygon has actually no angles pointing inwards. An ext precisely, no internal angle deserve to be much more than 180°.

If any kind of internal edge is better than 180° climate the polygon is concave. (Think: concave has a "cave" in it)

 Convex Concave

### Simple or Complex

A simple polygon has actually only one boundary, and it doesn"t cross over itself. A complex polygon intersects itself! many rules around polygons don"t work-related when the is complex.

 Simple Polygon(this one"s a Pentagon) Complex Polygon(also a Pentagon)

## More Examples

 Irregular Hexagon Concave Octagon Complex Polygon(a "star polygon",in this instance a pentagram)

## Play with Them!

Try Interactive polygons ... Make them regular, concave or complex.

## Names that Polygons

NameSidesShapeInterior Angle
 If the is a continuous Polygon... Triangle (or Trigon) 3 60° Quadrilateral (or Tetragon) 4 90° Pentagon 5 108° Hexagon 6 120° Heptagon (or Septagon) 7 128.571° Octagon 8 135° Nonagon (or Enneagon) 9 140° Decagon 10 144° Hendecagon (or Undecagon) 11 147.273° Dodecagon 12 150° Triskaidecagon 13 152.308° Tetrakaidecagon 14 154.286° Pentadecagon 15 156° Hexakaidecagon 16 157.5° Heptadecagon 17 158.824° Octakaidecagon 18 160° Enneadecagon 19 161.053° Icosagon 20 162° Triacontagon 30 168° Tetracontagon 40 171° Pentacontagon 50 172.8° Hexacontagon 60 174° Heptacontagon 70 174.857° Octacontagon 80 175.5° Enneacontagon 90 176° Hectagon 100 176.4° Chiliagon 1,000 179.64° Myriagon 10,000 179.964° Megagon 1,000,000 ~180° Googolgon 10100 ~180° n-gon n (n−2) × 180° / n

You deserve to make names making use of this method:

 Sides Start with... 20 Icosi... 30 Triaconta... 40 Tetraconta... 50 Pentaconta... 60 Hexaconta... 70 Heptaconta... 80 Octaconta... 90 Enneaconta... 100 Hecta... etc..See more: 1998 Ford Expedition Vacuum Hose Diagram For Vacuum Hoses On 1990

Sides
...end with
+1
...henagon
+2
...digon
+3
...trigon
+4
...tetragon
+5
...pentagon
+6
...hexagon
+7
...heptagon
+8
...octagon
+9
...enneagon

Example: a 62-sided polygon is a Hexacontadigon

BUT, because that polygons v 13 or more sides, the is yes sir (and easier) to write "13-gon", "14-gon" ... "100-gon", etc.

## Remembering

A Quad Bike has 4 wheels

### Pentagon (5 Sides)

The "Pentagon" in Washington DC has 5 sides

### Hexagon (6 Sides)

Honeycomb has actually Hexagons

### Septagon (7 Sides)

Think Septagon is a "Seven-agon"

### Octagon(8 Sides)

An Octopus has actually 8 tentacles

### Nonagon (9 Sides)

Think Nonagon is a "Nine-agon"

### Decagon (10 Sides)

Think Decagon has actually 10 sides,just favor our Decimal system has actually 10 digits

interactive Polygons inner Angles of polygons Exterior angle of polygons 2D shapes (simpler page)