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If (sin x = -sin 70°, 0°

If (sin x = -sin 70°, 0° < x < 360°), determine the two possible values of x.

  • A.
    110°, 250°
  • B.
    110°, 290°
  • C.
    200°, 250°
  • D.
    250°, 290°
Correct Answer: Option D
Explanation

The value of the sine of an angle is negative in the third and fourth quadrant. Hence options A and B are not the options.

(sin 250 = -sin (250 – 180) = – sin 70)

(sin 290 = – sin (360 – 290) = – sin 70)