RA and RB are two tangents from a common point ‘R’ outside the circle with centre ‘O’, having a radius of 6 cm. If ∠ARB = 70°, find the measure of the angle AOB.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 110°
If ∠ARB = 70º , then ∠ARO = 35º
In Triangle(OAR) , ∠OAR = 90º and ∠ARB = 35º
∠ROA = 180 - 90 - 35 = 180 - 125 = 55º
Similarly, ∠ROB = 55º
Thus, ∠AOB = 110º