Mathematics

Problem

In a circle, chords AB and CD are equal in length. Points P and Q lie on the circumference on the same side of both chords. If

\angle APB = 42^{\circ}

and

\angle CQD = (2x + 6)^{\circ}

, find the value of

x

. a) 24 b) 18 c) 16 d) 21