Icosagon

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icosagon

Real quickly please A polygon with 20 sides is called an icosagon, please tell me what is a polygon with 21 sides called.
12: dodecagon, duodecagon: 13: triskaidecagon, tridecagon: 14: tetrakaidecagon, tetradecagon: 15: pentadecagon: 16: hexadecagon: 17: heptadecagon: 18: octadecagon: 19: enneadecagon: 20: icosagon
19: regular-enneadecagon   28.465: 20: regular-icosagon   31.569: 100: regular-hectagon   795.513: 1000: regular-chiliagon   79577.210: 10000: regular-myriagon   7957746.893
A polygon with twenty sides.
tetradecagon 15 pentakaidecagon, pentadecagon 16 hexakaidecagon, hexadecagon 17 heptakaidecagon 18 octakaidecagon 19 enneakaidecagon 20 icosagon 21
20: icosagon: 30: triacontagon: 40: tetracontagon: 50: pentacontagon: 60: hexacontagon: 70: heptacontagon: 80: octacontagon: 90: enneacontagon: 100: hectogon: 10000: myriagon
Polygons. A polygon is closed plane figure formed by the joining of three or more Icosagon
A 20-sided polygon. The regular icosagon is a constructible polygon, and the regular icosagon of unit side length has inradius r, circumradius R, and area A given byr=1/2(1+sqrt(5
Icosagon: 20 : 162° Triacontagon: 30 : 168° Tetracontagon : 40 : 171° Pentacontagon: 50 : 172.8° Hexacontagon : 60 : 174° Heptacontagon : 70 : 174.857° Octacontagon : 80 : 175.5°

Jack in the box free