SSC CHSL 2021 PYQ — Question 52

SSC CHSL - 15 April 2021 - Shift 1 • Quantitative Aptitude • Q52

AB is a diameter of the cirlce with centre O. The tangent at the point C on the cirlce meets AB produced at Q. If ∠\angleBAC = 34º , then the measure of ∠\angleCQA (in degrees) will be:

Show answer & explanation

Correct answer: A

Explanation

The correct answer is option 1 i.e. 22.

AO = CO = radius 

∠OCQ = 90°    [A tangent is perpendicular to the radius at the point of tangency] 

In triangle AOC, ∠OAC = ∠ACO = 34°     [∵Angles opposite to equal sides] 

⇒ ∠COQ = ∠OAC + ∠ACO = 2 × 34° = 68°     [∵External angle property] 

In triangle CQO, ∠COQ + ∠OCQ + ∠CQO = 180°    [∵Property of Angle sum]

⇒ 68° + 90° + ∠CQO = 180° 

⇒ ∠CQO = 180° - 158° = 22° 

∠CQA = ∠CQO = 22° 

Hence ∠CQA is 22°.