The lines joining the origin to the point of intersection of `x^2+y^2+2gx+c=0 and x^2+y^2+2fy-c=0` are at right angles ifA. `g^(2)+f^(2)=c`B. `g^(2)-f^(2)=c`C. `g^(2)-f^(2)=2c`D. `g^(2)+f^(2)=c^(2)`

The lines joining the origin to the point of intersection of `x^2+y^2+

1.	The lines joining the origin to the point of intersection of `x^2+y^2+2gx+c=0 and x^2+y^2+2fy-c=0` are at right angles ifA. `g^(2)+f^(2)=c`B. `g^(2)-f^(2)=c`C. `g^(2)-f^(2)=2c`D. `g^(2)+f^(2)=c^(2)`
Answer» Correct Answer - C

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