Sum of interior angles=(n-2)180
3060=(n-2)180
3060/180=n-2
17=n-2
n=17+2
n=19..
Pi is an irrational number meaning it has no end, 3.14 is just an estimate which means that it is not accurate.
Answer by JKismyhusbandbae: 6n-16
Arithmetic Formula: 
Use the following formula to determine any number in an arithmetic sequence:
an = a1 + d (n – 1)
a1 = the first term.
d = common difference
n = term number