Question

number of common tangent to a circle

Answer 1

If two circles r not intersecting each other then there r 4 common tangents.

If two circles r touching each other externally at a common point then there r 3 common tangents.

If two circles r intersecting at two distinct points then there are two common tangents.

If two circles r touching each other internally then there is only one common tangent.

If two circles r concentric then there r no common tangents.