Question 1071446
{{{sin(3x)+2-2=1.5-2}}}

{{{sin(3x)=-1/2}}}

That sine means angle points into Q3 or Q4.  (Refer to the Unit Circle.)


Your common reference angle is  30 degrees, but since the sine indicates Q3 or Q4, also refer to how this relates to 180 degrees and to 360 degrees.


{{{system(cross(3x=120),3x=210,or,3x=330)}}}, measure is degrees.
(fixed small mental visualization mistake)



ANSWER:
{{{system(x=70*degrees, or, x=110*degrees)}}}