Powering the ArduinoBT

I recently purchased the Arduino bluetooth for a robotics project. Since the project is wireless, I decided to use a 4.5volt battery pack to power the Arduino.
The battery pack has two wires, one black and one red. I read online that they are both signal wires, and that I will not need a ground. If this is the case, do I send both wires to the V+ input on the Arduino board? Or, is it something else?
Thanks,
-Alex

"I read online that they are both signal wires, and that I will not need a ground." That cannot be correct.

Use a meter and confirm the red is +4.5 when the black is connected to Common on your meter.
Then connect the red wire to the 5V pin on your board, and black to GND.