The interior angle of a regular polygon is 156o. Find the number of sides of the polygon.
Let the number of sides of the regular polygon be n.
So, Interior angle of the regular polygon =[n−2]n×180o
Given, Interior angle =156o
So, [n−2]n×180o=156o
⇒180n−360=156n
⇒180n−156n=360
⇒24n=360
⇒n=36024
⇒n=15
Therefore, the regular polygon with a interior angle of 156o has 15 sides.