1-Open new file and enable polyline tool.
2-Draw start point then enter relative angle in the inspector bar,line segment moves accordingly.
3-Select Arc segment of polyline from local menu and Draw start point of arc polyline and select "direction" from inspector bar,relative angle field appears.
4-Enter relative angle and press finish polyline disappears.

Correct Sequence:
1) First click - defines arc start
2) Switch On "Direction" mode
3) Input angle -enter
4) drag and click to define arc end
5) finish