Answer:
D. 270°
Explanation:
The equation can be factored as ...
... (2sin(x) -1)(sin(x) +1) = 0
Then solutions are ...
... sin(x) = 1/2 . . . . x = 30°, 150° . . . . these values make the first factor 0
... sin(x) = -1 . . . . . x = 270° . . . . . . . this value makes the second factor 0