Question 969610
Note carefully how you are told to use x.  Year 2009 is for x=0. 

Now identify two data points, (x,y).  These are (0, 3.4) and  (5, 42.8).
Find the equation of the line that contains these two points.


{{{m=(42.8-3.4)/(5)}}}
{{{m=7.88}}}


Using the point-slope form, picking the first point,
{{{y-3.4=7.88(x-0)}}}
{{{highlight(y=7.88x+3.4)}}}-------now in slope-intercept form.