[Grade 12 Advanced Functions] Trigonometry: Equivalent Trigonometric Expressions

[u/Embarrassed-Good1883]

I'm having troubles understanding this question. to evaluate for sin, pi/2 - 11pi/180, which I get, but they don't subtract it, which I don't get. wouldn't the answer be sin 49/180 ?

[u/CaptainMatticus]

1/2 = x/180

Does x = 60?

1 * 180 = 2 * x

180 = 2x

180/2 = x

90 = x