Answer:
21°
Step-by-step explanation:
Assumed AOC is a straight line.
⇒ ∠AOC = 180°
Since ∠AOC = 180°
⇒ ∠BOC = 180 - 138 = 42°
Angle at the centre of the circle is twice the angle at the circumference.
∠BAC = 1/2 of BOC
Since ∠BAC = 1/2 of BOC
⇒ ∠BAC = 1/2 (42) = 21°
Angle BOC = 180 - 138 = 42
Angle on the circumference is half the angle at the centre
angle BAC = ½ × angle BOC
= ½ × 42
= 21°
