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Find the Coordinates of the Centre and Radius of Each of the Following Circles: X2 + Y2 + 6x − 8y − 24 = 0

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Question

Find the coordinates of the centre and radius of each of the following circles:  x2 + y2 + 6x − 8y − 24 = 0

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Solution

(i) The given equation can be rewritten as

\[x^2 + y^2 + 2\left( 3 \right)x - 2\left( 4 \right)y - 24 = 0\]
∴ Centre = \[\left( - 3, - 4 \right)\]
And, radius = \[\sqrt{\left( 3 \right)^2 + \left( 4 \right)^2 + 24} = \sqrt{49} = 7\]
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Advanced Concept of Circle - Standard Equation of a Circle
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Chapter 24: The circle - Exercise 24.2 [Page 31]

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R.D. Sharma Mathematics [English] Class 11
Chapter 24 The circle
Exercise 24.2 | Q 1.1 | Page 31

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