The lengthen command in AutoCAD is used to change the length of an object, such as a line, arc, polyline, or spline. This command allows you to extend, shorten, or modify the total length or included angle of objects.
To use the lengthen command:
Type LENGTHEN or LEN in the command line.
Select the object you want to modify.
Choose one of the lengthening options:
Delta: Specify the amount to add or subtract from the length.
Percent: Change the length by a percentage of the original length.
Total: Set a specific total length for the object.
Dynamic: Use the cursor to interactively change the length.
Enter the required value or use the mouse to apply the change.
The lengthen command is useful for precise adjustments to objects' dimensions in a drawing.