Question
Question: How many common tangents can be drawn to the following circles x<sup>2</sup> + y<sup>2</sup> = 6x an...
How many common tangents can be drawn to the following circles x2 + y2 = 6x andx2 + y2 + 6x + 2y + 1 = 0
A
4
B
3
C
2
D
1
Answer
4
Explanation
Solution
C1(3, 0) r1 = 3
C2(–3, –1) r2 = 3
C1C2 = 36+1 = 37
C1C2 > |r1 + r2|
Ž 4 common tangents