SSC CPO SI and ASI Model Paper 9

(1) Since angle ACB is 30 degrees,angle AOB will be 2 × 30° = 60°.
Now in triangle OAB, OA = OB (bothare radius),
∴∠OAB = ∠OBA = 60°
so, triangle OAB is an equilateraltriangle.
Therefore, OA = OB = AB⇒ x = 20 cm