CircleHard
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
View Solution FreeMore Circle Questions
If 2f(tx)dt = f(x) +1, where f(x) is non constant function, then y = f(x) represents -...What is the length of shortest path by which one can go from (-2, 0) to (2, 0) without entering the interior of circle, ...Equations of circles which pass through the points (1, _2) and (3, _ 4) and touch the x-axis is...The equation of the normal to the ellipse = 1 at the positive end of latus rectum is -...The equation of circles passing through (3, _6) touching both the axes is...