1. HOMEWORK: Complete ‘Name That Polygon’ Activities WS
Naming Polygons
HOMEWORK: Complete ‘Name That Polygon’ Activities WS

2. Naming a polygon by its number of sides requires that we know the appropriate Greek prefixes along with some rules for their use.

3. 3 through 20 sides, simply add "gon" to the prefixes to the right =
tri 4
tetra 5
penta 6
hexa or sexa 7
hepta 8
octa 9
nona 10
deca 11
undeca 12
dodeca 13
triskaideca 14
tetradeca 15
pentadeca 16
hexadeca 17
heptadeca 18
octadeca 19
enneadeca 20
icosa
For polygons with
3 through 20 sides, simply add "gon" to the prefixes to the right 
- although a trigon is more commonly called a triangle and a tetragon, a quadrilateral!

4. SIDES To "construct" a name, we start with the prefix for the tens digit, follow it by "kai" (the Greek word for "and"),
then follow it with the prefix for the units digit,
and finally add "gon."
Example: A 35-sided polygon is called a "triacontakaipentagon." 30
and 5
gon
triaconta
kai
penta

5. For more than 20 sides, we "construct" the name by combining prefixes:
Tens Digit 20 =
icosi 30
triaconta 40
tetraconta 50
pentaconta 60
hexaconta 70
heptaconta 80
octaconta 90
enneaconta
Ones Digit 1 =
hena 2 di 3
tri 4
tetra 5
penta 6
hexa 7
hepta 8
octa 9
ennea +
25 = icosi + kai + penta+ gon = icosikaipentagon
77 = heptaconta + kai + hepta + gon = heptacontakaiheptagon

6. 100 - 999 SIDES For numbers from 100 to 999, we need one more combining prefix and another rule.
To "construct" the name, we start with the prefix for the hundreds digit taken from the "Ones Digit" table above, follow it by "hecta," then proceed as before.
Example: A 672-sided polygon is called a "hexahectaheptacontakaidigon."
100 =
hecta
600 70
and 2
gon
hexa + hecta
heptaconta
kai di

7. Now you try some
914 sides
75 sides
753 sides

8. Triskaidecagon 13
Tetrakaidecagon 14
Pentadecagon 15
Hexakaidecagon 16
Heptadecagon 17
Octakaidecagon 18
Enneadecagon 19

9. Icosagon 20
Triacontagon 30
Tetracontagon 40
Pentacontagon 50
Hexacontagon 60
Heptacontagon 70
Octacontagon 80

10. Enneacontagon 90
Hectagon
100
Chiliagon
1,000
Myriagon
10,000
Megagon
1,000,000
Googolgon
10100

11. Hectagon
100
Chiliagon
1,000
Myriagon
10,000
Megagon
1,000,000
Googolgon
10100

12. How many sides?? Tetracontakaihexagon Icosikaioctagon
Octacontakaihexagon
Heptacontakaitrigon
Octacontakaitrigon
Dihectapentacontakaiheptagon
Enneahectaenneacontakaienneagon