CircleEasy
Question
The number of common tangents to the circle
x2 + y2 - 4x - 6y - 12 = 0 and
x2 + y2 + 6x + 18y + 26 = 0, is :
x2 + y2 - 4x - 6y - 12 = 0 and
x2 + y2 + 6x + 18y + 26 = 0, is :
Options
A.3
B.4
C.1
D.2
Solution
distance between centres (c1c2) = 13 r1 =
= 5 & r2 = 
= 8 c1c2 = r1 + r2 is a case of external touching (as shown in above figure), so three common tangents can be drawn.Create a free account to view solution
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