About Editing Curves
Edit a curve by modifying its points. Use the Curve Edit tool to add, remove, and move points.
You can apply a movement constraint to any point, and then drag the point. You can also nudge a point by a small increment, according to the movement constraint you set. Place a point in an exact location in one of the following ways:
Define point coordinates.
Specify a distance ratio between two endpoints.
Set a distance from an endpoint.
Snap the point to a reference or to another entity in the Style feature.