Question
Question: The locus of the centre of a circle which touches externally the circle x<sup>2</sup> + y<sup>2</sup...
The locus of the centre of a circle which touches externally the circle x2 + y2 – 6x – 6y + 14 = 0 and also touches the y-axis is given by the equation –
A
x2 – 6x – 10y + 14 = 0
B
x2 – 10x – 6y + 14 = 0
C
y2 – 6x – 10y + 14 = 0
D
y2 – 10x – 6y + 14 = 0
Answer
y2 – 10x – 6y + 14 = 0
Explanation
Solution
x2 + y2 – 6x – 6y + 14 = 0 ...(1)
Ž C1(3, 3) , r1 = 2
Locus of centre C2(h, k) = ?
Q C2N = r2 = |h| Ž C1C2 = (r1 + r2)
Q Both the circles touches each other externally.