COMEDK2024MathematicsCircle
The radius and centre of circle which equation is 3 x^2+3 y^2+6 x+12 y+5=0 is
Options
- A(-3,-4), 20
- B(3,4), 20
- C(-1,-2), 5 2 3
- D(1,2), 5 2 3
Correct answer
C. (-1,-2), 5 2 3
Step-by-step solution
If equation of circle is x^2+y^2+2 g x+2 f g+c=0 Then, centre =(-g,-f) aligned & Radius = g^2+f^2-c & x^2+y^2+2 x+4 y+ 5 3 =0 aligned aligned & Centre =(-g,-f)=(-1,-2) & Radius = 1^2+2^2- 5 3 = 5- 5 3 =5 2 3 aligned