AP EAMCET2009MathematicsCircle
The locus of centre of a circle which passes through the origin and cuts off a length of 4 unit from the line x=3 is
Options
- Ay^2+6 x=0
- By^2+6 x=13
- Cy^2+6 x=10
- Dx^2+6 y=13
Correct answer
B. y^2+6 x=13
Step-by-step solution
Let centre of circle be C(-g,-f) , then equation of circle passing through origin be x^2+y^2+2 g x+2 f y=0 array lc Distance, d=|-g-3|=g+3 In A B C, & (B C)^2=A C^2+B A^2 & g^2+f^2=(g+3)^2+2^2 & g^2+f^2=g^2+6 g+9+4 & f^2=6 g+13 array Hence, required locus is y^2+6 x=13