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MHT CET · Maths · Circle

The number of common tangents to the circles \(x^2+y^2-4 x-6 y-12=0\) and \(x^2+y^2+6 x+18 y+26=0\), is

  1. A 1
  2. B 2
  3. C 3
  4. D 4
Verified Solution

Answer & Solution

Correct Answer

(C) 3

Step-by-step Solution

Detailed explanation

\(C_1=(2,3), r_1=\sqrt{2^2+3^2-(-12)}=\sqrt{4+9+12}=\sqrt{25}=5\) \(C_2=(-3,-9), r_2=\sqrt{(-3)^2+(-9)^2-26}=\sqrt{9+81-26}=\sqrt{64}=8\)