Mathematics

Problem

Chord AB of a circle subtends an angle of

30^{\circ}

at point C on the circle and an angle of

x^{\circ}

at point D, where C and D lie on the same segment formed by AB. Which one of the following is the value of

x

? a)

60^{\circ}

30^{\circ}

15^{\circ}

90^{\circ}