point-slope form of a line:
where m is the slope and (x1, y1) is a point on the line.
In the case of:
the slope is 1/5 and the point is (1, 2)
With this information, we can deduce that the point (1+5, 2+1) = (6, 3) is on the line. Connecting these two points we can graph the line as follows: