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

Enter a value (in degrees) for the start angle and press 
<Enter>, or accept the default value in parentheses by
pressing <Enter>.

Enter a value (in degrees) for the end angle and press
<Enter>, or accept the default value in parentheses by
pressing <Enter>.

Select the desired tangent entity, near the point of 
tangency. If necessary, you can cancel the selection by
choosing the BACK-UP option and selecting another entity.

Indicate a position for the center of the arc by selecting
an option from the Position Menu.

If a tangent arc cannot be created (for example, because 
the indicated center position is on the selected tangent 
entity), an error message is displayed. You are prompted
to press <Enter> and to select a different tangent entity.

In 2-D construction mode, the arc is created in the 
construction view, at the depth that is active when the 
center is indicated.

In 3-D construction mode, the arc is created in the plane
of the selected entity and the indicated point.

To create another arc tangent to the selected entity,
indicate another center position.
