We find the **reference angle **first.

Let sin *α* = 0.8480, then we have

α= arcsin 0.8480 = 58.0°

Since `sin\ theta`* *is negative, *θ* must be in Quadrants III or IV.

So *θ* = 180° + 58.0° = 238.0° or

*θ* = 360° − 58.0° = 302.0°

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