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Question
The equation x2 + y2 + 2x − 4y + 5 = 0 represents
Options
a point
a pair of straight lines
a circle of non-zero radius
none of these
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Solution
a point
The radius of the given circle = \[\sqrt{1^2 + \left( - 2 \right)^2 - 5} = 0\]
Hence, the radius of the given circle is zero, which represents a point.
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