Respostas

2014-03-27T22:43:31-03:00
180º.(n-2) = 1260 ⇒ n - 2 = 7 ⇒ n = 9 ⇒ eneágono

d= \frac{n.(n-3)}{2} =\frac{9.(9-3)}{2}=\frac{9.(6)}{2}=9.3=27 diagonais
2014-03-27T22:43:44-03:00
180(n-2)=Si
180(n-2)=1260
n-2=1260 : 180
n-2=7
n=7+2
n=9