ExamBro
ExamBro
TS EAMCET · Maths · Circle

If a circle C passing through the point (4,0) touches the circle x2+y2+4x-6y=12 externally at the point (1,-1), then the radius of C is

  1. A 5
  2. B 25
  3. C 57
  4. D 4
Verified Solution

Answer & Solution

Correct Answer

(A) 5

Step-by-step Solution

Detailed explanation

Given equation of circle : x2+y2+4x-6y=12 Now equation of tangent to this circle at 1,-1 is T=0⇒x-y+4 x+12-6 y-12=12 ⇒x-y+2x+2-3y+3=12 ⇒3x-4y-7=0 Now equation of circle touching the line 3x-4y-7=0 at 1, -1 is…