Respostas

  • Usuário do Brainly
2014-08-04T20:21:40-03:00
Sn=180.(n-2)
i = Sn/n
i=180(n-2)/n
150n=180(n-2)
180n-360=150n
30n=360
n=12

d=n(n-3)/2
d=12.9/2
d=6.9
d=54
9 3 9