The size of an interior angle of a regular polygon is 3x° while its exterior angle is (x- 20)°. Find the number of sides of the polygon

Answer 1

first let's find value of x where
3x°+(x-20)°=180°

3x +x -20 =180

4x=180+20

4x=200

4x/4=200/4
x=50°
then number of sides = 360/(exterior angle)
of a regular polygony

therefore sizes=360/30

sides= 12

Answer 2

7.2

Answer 3

12