Question

Angle C is inscribed in circle O.

AB is a diameter of circle O.
What is the measure of ZB?

Answer 1

∠ B = 19°

Explanation:

note ∠ C = 90° ( angle in a semi- circle )

The sum of the 3 angles in the triangle = 180°, thus

∠ B = 180° - (90 + 71)° = 180° - 161° = 19°