Question

WZ←→ is tangent to circle O at point B.

What is the measure of ∠OBZ?


80º

90º

160º

180º

Answer 1

The measure of angle ∠OBZ is 90°, as the tangent line to a circle at a point is perpendicular to the radius at that point.

Step-by-step explanation:

The question regards the measure of angle ∠OBZ where WZ↔ is tangent to circle O at point B. By a well-known theorem in geometry, a line tangent to a circle is perpendicular to the radius drawn to the point of tangency. Therefore, the measure of angle ∠OBZ, which is formed by the radius OB and the tangent line at B, must be 90°.

Answer 2

The correct option is 2.

Step-by-step explanation:

Given information: WZ is tangent to circle O at point B.

According to the tangent of circle theorem: The tangent line is perpendicular to the radius at the point of tangency. It means the angle formed on the point of tangency by tangent and radius is a right angle.

Since WZ is tangent to circle O at point B and OB is radius, therefore

`\angle OBZ=90^(\circ)`

Therefore correct option is 2.