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AP EAMCET · Maths · Circle

If power of a point \((4,2)\) with respect to the circle \(x^2+y^2\) \(-2 \alpha x+6 y+\alpha^2-16=0\) is 9 , then the sum of the lengths of all possible intercepts made by such circles on the coordinate axes is

  1. A \(16+4 \sqrt{6}\)
  2. B \(16+4 \sqrt{6}-6 \sqrt{2}\)
  3. C \(16+4 \sqrt{6}+6 \sqrt{2}\)
  4. D \(16+6 \sqrt{2}\)
Verified Solution

Answer & Solution

Correct Answer

(A) \(16+4 \sqrt{6}\)

Step-by-step Solution

Detailed explanation

\(x^2+y^2-2 \alpha x+6 y+\alpha^2-16=0\) Centre \((C)=(\alpha,-3) ;(x-\alpha)^2+(y+3)^2=25\) Radius \((R)=5\) \(d=\) distance between centre and \((4,2)\) \(\Rightarrow d^2=(\alpha-4)^2+25\) Power \(=d^2-R^2 \Rightarrow 9=(\alpha-4)^2 \mathrm{~m} \Rightarrow \alpha=1,7\) When…