Respostas

2013-12-12T18:31:11-02:00
Ê = 360/n
360/n = 20
20n = 360
n = 360/20
n = 36/2
n = 18 (18 lados)

d = n.(n-3)/2
d = 18.(18-3)/2
d = 9.15
d = 135 (135 diagonais)
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