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Question
Equation of the diameter of the circle x2 + y2 − 2x + 4y = 0 which passes through the origin is
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x + 2y = 0
x − 2y = 0
2x + y = 0
2x − y = 0Let the diameter of the circle be y = mx.
Since the diameter of the circle passes through its centre, (1, −2) satisfies the equation of the diameter.
∴
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Solution
2x + y = 0
Let the diameter of the circle be y = mx.
Since the diameter of the circle passes through its centre, (1, −2) satisfies the equation of the diameter.
∴ \[m = - 2\]
Substituting the value of m in the equation of diameter:
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