Fermi
·
Concept Library
·
Courses
·
Books
·
Problems
·
Simulations
·
Math Wiki
·
High School
Fermi
›
Problems
Mathematics
Mathematics
Problem
If a circle C passing through
(
4
,
0
)
(4, 0)
(
4
,
0
)
touches the circle
x
2
+
y
2
+
4
x
−
6
y
−
12
=
0
x^2 + y^2 + 4x - 6y - 12 = 0
x
2
+
y
2
+
4
x
−
6
y
−
12
=
0
externally at a point
(
1
,
−
1
)
(1, -1)
(
1
,
−
1
)
, then the radius of the circle C is : (1)
57
\sqrt{57}
57
(2)
2
5
2\sqrt{5}
2
5
(3) 4 (4) 5
Browse the problem library