Question

The ratio of interior and exterior angle of regular polygon is is 5:1, find the number of diagonals of the regular polygon. *
1 point
A}15
B}10
C}9
D}12
any wrong an s or spamming something for points will be reported to the moderator

Answer 1

Answer:

Correct option is

A

9

Interior angle of a polygon of n-sides =

n

(n−2)π

Exterior angle of a polygon of n-sides =

n

2π

Taking there ratio, and equating it to

2

7

Thus

2

n−2

=

2

7

⇒n=9