Method A

  1. Drag a circle from the tool bar and pause over the intersection point of two lines. Wait for the popup to show you the attachment options and then select “intersection of lines.”
  2. Release and drag again to define the radius of the circle.
  3. The circle is now attached to the intersection point. Moving the endpoint of either line or moving the entire line will move the circle.

Interactive Geometry - Example - Circle Attaching to Two Lines

Interactive Geometry - Example - Circle Attached to Two Lines