To Label the Length and Direction of a Line

Select the Element Dimensioning tool ( Drawing > Annotate > Dimensioning ).
Select the line to be dimensioned.

If Location is set to Automatic or if it is an association point, this point will position the label origin.
Set the mode to Label Line.
Enter a data point to position the label origin.

Figure 1. Labeling the length and direction of a line

Note: To reverse an element's direction, use the Change Curve Direction tool.

Note: To get angle to display in bearing mode, switch the Angle Format Display option on the Units tab in the Dimension Styles dialog.