AB and CD are two chords in a circle with centre O and AD is a diameter. AB and CD produced meet at a point P outside the circle. If ∠APD = 25º and ∠DAP = 39º, then the measure of ∠CBD is:
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 26º
∠ADC = 25 + 39 = 64° (Exterior angle sum property)
∠ADC = ∠ABC = 64° (Angle on the same segment)
AD is the diameter here,
∠ABD = 90°
∠CBD = 90 - 64 = 26°.