Question 590944
<pre>
The other tutor just gave you the answer but didn't show you how
to get it.

Here is A and B:
             {{{drawing(200,350,-.5,1.5,-2,1.5,
circle(1.5cos(48*pi/180),-1.5sin(48*pi/180),.02),
 circle(0,0,.02),
locate(-.1,0,A), locate(1.5cos(48*pi/180)+.02,-1.5sin(48*pi/180)-.05,B) )}}}

Draw a line connecting them.

             {{{drawing(200,350,-.5,1.5,-2,1.5,
circle(1.5cos(48*pi/180),-1.5sin(48*pi/180),.02),
 circle(0,0,.02),


locate(-.1,0,A), locate(1.5cos(48*pi/180)+.02,-1.5sin(48*pi/180)-.05,B),line(0,0,1.5cos(48*pi/180),-1.5sin(48*pi/180)) )}}}

From A we draw a line of arbitrary length vertically upward (in green) 
to indicate the direction of north from A. 
             {{{drawing(200,350,-.5,1.5,-2,1.5,

circle(1.5cos(48*pi/180),-1.5sin(48*pi/180),.02),
 circle(0,0,.02),

locate(-.1,0,A), locate(1.5cos(48*pi/180)+.02,-1.5sin(48*pi/180-.05),B), 
green(line(0,0,0,1)),line(0,0,1.5cos(48*pi/180),-1.5sin(48*pi/180)),
green(locate(0,1.1,N)))}}}</pre>
>>...the bearing of A to B is 138°...<<<pre>
That means that if we measure the angle indicated by the red arc below
IN THE CLOCKWISE direction, we find that this clockwise angle measures 
138°: 


             {{{drawing(200,350,-.5,1.5,-2,1.5,
red(arc(0,0,.5,-.5,312,450),locate(.3,.1,"138°")),
circle(1.5cos(48*pi/180),-1.5sin(48*pi/180),.02),
 circle(0,0,.02),

locate(-.1,0,A), locate(1.5cos(48*pi/180)+.02,-1.5sin(48*pi/180-.05),B), 
green(line(0,0,0,1)),line(0,0,1.5cos(48*pi/180),-1.5sin(48*pi/180)),

green(locate(0,1.1,N))


  )}}}
Next we do a similar thing at B.  From B we draw a line of arbitrary length
vertically upward (also in green) to indicate the direction of north from B.



             {{{drawing(200,350,-.5,1.5,-2,1.5,
red(arc(0,0,.5,-.5,312,450),locate(.3,.1,"138°")),
circle(1.5cos(48*pi/180),-1.5sin(48*pi/180),.02),
 circle(0,0,.02), green(locate(1,.05,N)),

locate(-.1,0,A), locate(1.5cos(48*pi/180)+.02,-1.5sin(48*pi/180-.05),B), 
green(line(0,0,0,1)),line(0,0,1.5cos(48*pi/180),-1.5sin(48*pi/180)),
green(line(1.5cos(48*pi/180),-1.5sin(48*pi/180),1,0)),
green(locate(0,1.1,N))


  )}}}

We are to find the number of degrees in the CLOCKWISE measured angle 
from A to B, indicated by the other red arc below:

             {{{drawing(200,350,-.5,1.5,-2,1.5,
red(arc(0,0,.5,-.5,312,450),locate(.3,.1,"138°")),
circle(1.5cos(48*pi/180),-1.5sin(48*pi/180),.02),
 circle(0,0,.02), green(locate(1,.05,N)),

locate(-.1,0,A), locate(1.5cos(48*pi/180)+.02,-1.5sin(48*pi/180-.05),B), 
green(line(0,0,0,1)),line(0,0,1.5cos(48*pi/180),-1.5sin(48*pi/180)),
green(line(1.5cos(48*pi/180),-1.5sin(48*pi/180),1,0)),
green(locate(0,1.1,N)),


red(arc(1.5cos(48*pi/180),-1.5sin(48*pi/180),.5,-.5,132,450))


  )}}}

What angle does that second red arc indicate the measure of?

To find out, one easy way is to extend the line from A to B at B, 
like this:

             {{{drawing(200,350,-.5,1.5,-2,1.5,
red(arc(0,0,.5,-.5,312,450),locate(.3,.1,"138°")),
circle(1.5cos(48*pi/180),-1.5sin(48*pi/180),.02),
 circle(0,0,.02), green(locate(1,.05,N)),

locate(-.1,0,A), locate(1.5cos(48*pi/180)+.02,-1.5sin(48*pi/180-.05),B), 
green(line(0,0,0,1)),line(0,0,1.5cos(48*pi/180),-1.5sin(48*pi/180)),
green(line(1.5cos(48*pi/180),-1.5sin(48*pi/180),1,0)),
green(locate(0,1.1,N)),

line(0,0,1.9cos(48*pi/180),-1.9sin(48*pi/180)),


red(arc(1.5cos(48*pi/180),-1.5sin(48*pi/180),.5,-.5,132,450))


  )}}}

Then we can see that the angle indicated by the blue arc below is 
also 138°, because the two green lines are parallel and the 
transversal AB cuts them at B.  Then the rest of the angle indicated
by the red arc is 180°, so we add the two together: 

             {{{drawing(200,350,-.5,1.5,-2,1.5,
red(arc(0,0,.5,-.5,312,450),locate(.3,.1,"138°")),
circle(1.5cos(48*pi/180),-1.5sin(48*pi/180),.02),
 circle(0,0,.02), green(locate(1,.05,N)),

locate(-.1,0,A), locate(1.5cos(48*pi/180)+.02,-1.5sin(48*pi/180-.05),B), 
green(line(0,0,0,1)),line(0,0,1.5cos(48*pi/180),-1.5sin(48*pi/180)),
green(line(1.5cos(48*pi/180),-1.5sin(48*pi/180),1,0)),
green(locate(0,1.1,N)),

line(0,0,1.9cos(48*pi/180),-1.9sin(48*pi/180)),

blue(arc(1.5cos(48*pi/180),-1.5sin(48*pi/180),.7,-.7,312,450)),

red(arc(1.5cos(48*pi/180),-1.5sin(48*pi/180),.5,-.5,132,450))


  )}}}

So the bearing from B to A is 138° + 180° or 318°.

Edwin</pre>.