HDMI to DVI for macbook

So I bought the mini DVI to DVI adapter along with the HDMI to DVI video cable...i have it all connected and the tv is on the right input but it still will not show up. I wasn't sure what all I needed to do with the displays because display properties come up for both the tv and macbook, not sure where to go from there?! and if mac's are like pc's where you need to press function something to show up on the other screen...can anybody help me out with this? thank u!

Just grab the top bar of the window and drag it towards the right side of the MB. The TV is your display extension.