Answer:
The measure of m∠B = 19°.
Step-by-step explanation:
Given
- Angle C is inscribed in circle O.
As we know that an angle inscribed in a semicircle is always a right angle.
So from the given diagram,
As we know that the sum of the three interior angles is equal to 180.
so
m∠A + m∠B + m∠C = 180°
71° + m∠B + 90° = 180°
m∠B = 180° - 71° - 90°
m∠B = 19°
Therefore, the measure of m∠B = 19°.
