To graph the line we need two points; we already have one the point (4,2) now we need to find another one; to do this we get the equation of the line given by:

where m is the slope and (x1,y1) are a point throught the line. Plugging the values given we have:

Now we give a value to x and find the corresponding y. If x=0, then:

hence we have the point (0,-2).
Now that we have two points (0,-2) and (4,2) we graph them on the plane and join them with a straight line, hence the graph is: