Answer:
Explanation:
8) a) No: of sides of a regular polygon = 360° / exterior angle
= 360°/18° = 20 sides
b) Sum of interior angles of regular polygon = (n-2) * 180° {n-no:of sides}
= (20-2)*180° = 18*180° = 32400°
9) Let the exterior angle be x.
So, interior angle = 140° + x
Interior angle + exterior angle = 180°
140° +x + x = 180°
140° +2x = 180°
2x = 180° - 140°
2x =40°
x = 40°/2 = 20°
Exterior angle = 20°
Interior angle = 160°
No: of sides of a regular polygon = 360° / exterior angle
= 360°/20° = 18 sides
Hint: Always sum of exterior angles of regular polygon is 360°