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Question
Find the centre and radius of each of the following circles:
(x − 1)2 + y2 = 4
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Solution
Let (h, k) be the centre of a circle with radius a.
Thus, its equation will be
Given:
(x − 1)2 + y2 = 4
Here, h = 1, k = 0 and a = 2
Thus, the centre is (1, 0) and the radius is 2.
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