1978
JEE Advanced
Numerical
IIT-JEE 1978
Find the equation of the circle whose radius is 5 and which touches the circle ${x^2}\, + \,{y^2}\, - \,2x\,\, - 4y\, - 20 = 0\,$ at the point (5, 5).
Correct Answer: $${x^2}\, + \,{y^2}\, - \,18x\,\, - 16y\, + 120 = 0\,$$