VCS Tech Support : 
by Sherry Surrett
How many times have you hit the “Home” button to close a sketch to get that final pesky angle of the house, only to know that you need to sketch another item against that angled line?
Of course, you can use the Trace Feature to trace that entire line, as shown below.
However, what if the new line you are drawing doesn’t extend the full length of the line and only goes part of the way? How do you get that partial line on the same angle?
I suggest you use the radial line 
or Ctrl + R for my keyboard enthusiasts. Once in radial drawing mode, press the Page Up or Page Down button to display the hidden arrow (blue arrow as shown below).
Now, as the instructions below indicate, use the Page Up or Page Down arrow to move that blue arrow in 45 degree increments, press the Ctrl Key with Page Up or Page Down to move that arrow at 5 degree increments, or press the Alt Key with Page Up or Page Down to move that arrow at a 1 degree increment.
Continue using the various combinations until the blue arrow lines up to the angle you wish to draw, and press Enter.
Next, type the length of the line you want to draw, and press Enter. Press Enter one more time to confirm the line.
Continue on with your sketch, repeating the process as necessary, and press Home to complete it.
