To Extend or Shorten a Line by Entering a Data Point

Select the Extend tool (Drawing > Home > Modify > More split button ).

Select the line near the endpoint to modify.

Do one of the following:

If Distance is on, specify the desired distance and enter a data point to accept the modification.

or

If Distance is off, enter a data point to define the new endpoint.

Top: Defining the new endpoint graphically when Distance is off \ Bottom: Defining the new endpoint when Distance is on.

Note: If the Distance, denoted by D, is negative, the line is shortened. If the Distance is positive, the line is lengthened.