Q2 of 31 Page 218

The tangent drawn at points P and Q on the circumference of a circle intersect at A. If ∠PAQ = 60°, let us find the value of ∠APQ.

circle-tangent.png


PAQ = 60


AQ = AP (Tangent drawn from an external source to the same circle are always equal in length)


So Δ PQA is isosceles triangle


∠ AQP = ∠ APQ = x (Let)


Since sum of interior angles of a triangle = 1800,so we can say,


2x + 600 = 1800


⇒ 2x = 1200


⇒ x = 600


∠ APQ = 600


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