Answer:
18 sides
Step-by-step explanation:
Given the interior angle of a regular polygon, we can find that the exterior angles are (180°-interior°). And the number of sides of the polygon times the exterior angles must equal 360°. So we can write:
(180-160)°•(n)=360°
(20°)•(n)=360°
n=(360/20)°
n=18 sides