When drawing relative lines at angles.  for example I draw a line from 0,0 to @12'<0.  I then want to draw the following line, but cannot figure it out @0'3-1/2"90.  I have tried @0'-3-1/2";<90 which is not accepted and I have tried @0'-3 1/2"<90 but it doesn't like the space.  I have tried 3-1/2"<90 as well.  How do I do this.  This is the most used style of drafting I do.