Airplay with a MacBook late 2008 aluminum

Hello

I'd like to purchase an Apple TV to use the AirPlay function but I'm getting mixed messages on if my MacBook will be able to do it. It's a late 2008 13" aluminum MacBook which isn't on the list of MacBook's compatible for AirPlay, however on the same apple page it told me if I checked under system preferences and the "show mirroring options in menu bar when available" option that it will work, which I have that. I can use my current HDMI cable to use my tv screen as a monitor and can also use it and not mirror the displays so I can stream on my TV from my Mac but still use my Mac at the same time, I'd just like a wireless option as working with the cables is a pain.

I have updated my Mac and am running on OS X El Captain 10.11.4

Thank you in advance community!