TANGENT allows you to create a circle tangent to one, two 
or three entities.

Create a tangent circle by choosing from the following
options:


CTR-ENT - to create a circle tangent to a selected entity,
with its center at an indicated position.

2 ENTS - to create a circle tangent to two selected 
entities, with a specified radius.

3 ENTS - to create a circle tangent to three selected
entities.


When selecting entities, the selection point needs to be
near the desired point of tangency.

If a 2-D entity (i.e., arc, conic, or 2D spline) appears
as a straight line in the current view it cannot be 
selected in this function.

In 3-D construction mode, the selected entities must be
coplanar. Polylines, polygons, and 3-D splines cannot be
selected because they are not planar entities.

A tangency point may be on an extension of a selected
entity.
