Two circles, centred at P and Q, intersect at two points C and D. AB is tangent to the two circles at A and B. If ∠ADB = 68°, find the value of ∠ACB.
Question
Two circles, centred at P and Q, intersect at two points C and D. AB is tangent to the two circles at A and B. If ∠ADB = 68°, find the value of ∠ACB.