The TI-84 won't help you until you get the equation in
the form y = mx + b, and you have to find the equation 
all by yourself.

Get this in the form y = mx + b

2x + 3y = 4
     3y = -2x + 4
     y = x + 
      y = x + 

Compare to 

      y = mx + b

And you see that m = 

That's the slope of the given line and also the
slope of the desired line.  Next we use the
point-slope form of the equation of a line, 
which is:

y - y1 = m(x - x1)

Where m =  and (x1, y1) = (1,2)

y - 2 = (x - 1)

y - 2 = x + 

    y = x +  + 2

    y = x +  + 

    y = x +  

Now you can get the calculator to graph it.

Press Y=  and after \Y1= type

     -2/3X+8/3  so that it looks like this:

\Y1=-2/3X+8/3

Press ZOOM
Press 6

Then you see this:



Edwin