Resizing Arc Lines

You can resize arc lines using middle and end controls.

1. Select the arc.
   
2. Drag the end controls to change the arc length.
3. To change the radius of the arc while keeping the radius concentric, on the Options Bar, select Keep Concentric.

   Clear that option to retain an existing end condition, such as an end point location or tangency to a straight wall.

4. Drag the middle control.