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HOMEWORK: Complete ‘Name That Polygon’ Activities WS
Naming Polygons HOMEWORK: Complete ‘Name That Polygon’ Activities WS
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Naming a polygon by its number of sides requires that we know the appropriate Greek prefixes along with some rules for their use.
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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!
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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
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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
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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
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Now you try some 914 sides 75 sides 753 sides
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Triskaidecagon 13 Tetrakaidecagon 14 Pentadecagon 15 Hexakaidecagon 16 Heptadecagon 17 Octakaidecagon 18 Enneadecagon 19
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Icosagon 20 Triacontagon 30 Tetracontagon 40 Pentacontagon 50 Hexacontagon 60 Heptacontagon 70 Octacontagon 80
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Enneacontagon 90 Hectagon 100 Chiliagon 1,000 Myriagon 10,000 Megagon 1,000,000 Googolgon 10100
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Hectagon 100 Chiliagon 1,000 Myriagon 10,000 Megagon 1,000,000 Googolgon 10100
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How many sides?? Tetracontakaihexagon Icosikaioctagon
Octacontakaihexagon Heptacontakaitrigon Octacontakaitrigon Dihectapentacontakaiheptagon Enneahectaenneacontakaienneagon
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