To graph a function you must first select "Graph" tab, type in the function and click on "Solve".

Click here to see the graph. 

You can read the x-intercept and y-intercept from the graph:

You can find the intercepts by simply plaguing the values:

x = 0 for y-intercept

and

y = 0 for x-intercept

For x = 0 we find 3*0 - 2y = 8 that is y = -4, that is, the y-intercept is: (0, -4) 

For y = 0 we find 3*x - 2*0 = 8 that is x = 2 2/3, that is, the y-intercept is: (2 2/3, 0)