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Circle - Tangent to Entities
Creates a circle tangent to three objects (rectangles, polygons, arcs, etc.)
- Select the first tangent object.
- Select the second tangent object.
- Select the third tangent object. The tangent circle is created.
Local menu option:
Through point: Makes the circle pass through a specific point. In the example below, a vertex of the polygon was selected, rather than the polygon itself.
Tangent Circle of Fixed Size
By default, Tangent to Entities creates a circle that touches three objects. To fix the size of the circle, enter the radius, diameter, or circumference in the Inspector Bar and lock it, but do not press Enter. When you move the cursor, the circle size remains constant.
 Select the second tangent object, close to the point of tangency.
 The fixed-sized tangent circle is created.