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Question
Find the coordinates of the centre and radius of each of the following circles: x2 + y2 − ax − by = 0
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Solution
The given equation can be rewritten as
∴ Centre = \[\left( \frac{a}{2}, \frac{b}{2} \right)\]
And, radius =\[\sqrt{\left( \frac{a}{2} \right)^2 + \left( \frac{b}{2} \right)^2} = \frac{1}{2}\sqrt{a^2 + b^2}\]
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