VSA1 markYear: 2020MediumCBSE Class 10
circlestangentalternate-segment-theorem
Question
In Fig. 3, PQ is a chord of a circle and PT is tangent at P such that ∠QPT=60°, then the measure of ∠PRQ is ________.

Solution
1
∠QPT=60° (angle between tangent and chord). By alternate segment theorem, ∠QRP=60° (angle in alternate segment). But ∠PRQ is the angle in the major segment. ∠PRQ=180°−60°=120°
+1 mark