It is given that , each angle of a regular polygon measures 160 . And to check the polygon, we have to use the following formula
[tex] S= \frac{(n-2)180}{n} [/tex]
n is the number of sides
[tex] 160=\frac{(n-2)180}{n} [/tex]
Cross multiplication
160n = 180n -360
Subtracting 180n to both sides
-20n =-360
Dividing both sides by -20
n =18
So the polygon must have 18 sides