COMEDK2013MathematicsCircle
The value of k so that x²+y²+k x+4 y+2=0 and 2 (x²+y² )-4 x-3 y+k=0 cut orthogonally is
Options
- A10 3
- B- 8 3
- C- 10 3
- D8 3
Correct answer
C. - 10 3
Step-by-step solution
Given, circles can be written as x²+y²+k x+4 y+2=0 and x²+y²-2 x- 3 2 y+ k 2 =0 Since, both circles are orthogonal, then 2 g₁ g₂+2 f₁ f₂=c₁+c₂ -k-3=2+ k 2 3 k 2 =-5 k=- 10 3