Question 1063188
The exterior angles are x
The interior angles are x+120
the two add to 180 degrees.
Therefore, 2x+120=180
2x=60
x=30 degrees exterior angles
all of the exterior angles (n) add to 360 degrees,
Therefore, 360/30=12 sides
(n-2)*180 is their sum or 1800
150 degrees is an interior angle, and 12 of them add to 1800 degrees.