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Question
If the equation of a circle is λx2 + (2λ − 3) y2 − 4x + 6y − 1 = 0, then the coordinates of centre are
Options
(4/3, −1)
(2/3, −1)
(−2/3, 1)
(2/3, 1)
Solution
(2/3, −1)
To find the centre:
Coefficient of x2 = Coefficient of y2
\[\therefore \lambda = 2\lambda - 3 \Rightarrow \lambda = 3\]
Therefore, the given equation can be rewritten as
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