Mathematics
In figure (i) given below, O is the centre of the circle and AB is a tangent at B. If AB = 15 cm and AC = 7.5 cm, find the radius of the circle.
Circles
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Answer
Since the tangent at any point of a circle and the radius through the point are perpendicular to each other.
So, from figure,
OB ⊥ AB
In right angled △OBA,
Hence, radius of the circle = 11.25 cm.
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