Question 639677
<pre>
First we draw AM

{{{drawing(400,280,-3,17,-3,11,grid(1), green(line(3,9,9,7))

)}}}

To get from A(3,9) to M(9,7), we came DOWN 2 units, then went
RIGHT 6 units, as indicated by the red lines:

{{{drawing(400,280,-3,17,-3,11,grid(1), green(line(3,9,9,7)),
red(line(3,9,3,7),line(3,7,9,7))

)}}}

Therefore to get from M to B, we will also have to come DOWN
2 units, then go RIGHT 6 units, like this:

{{{drawing(400,280,-3,17,-3,11,grid(1), green(line(3,9,15,5)),
red(line(3,9,3,7),line(3,7,9,7)),
red(line(9,7,9,5),line(9,5,15,5))

)}}}

and we end up at B which has the coordinates B(15,5)

Edwin</pre>