I am trying to connect my bluetooth module to my Arduino but it takes 3.3 volts (the bluetooth module HC-05, The Arduino mega takes 5v) and the tutorials online say to connect the RX pin to the Ground through a voltage divider.

<https://www.youtube.com/watch?v=hyME1osgr7s>

i'm not sure how it works but i don't understand because if i'v learned anything by playing around with electronics it would be that you should never connect positive voltage to GND. I mean it's technically not connecting 5v to GND but it seems like a bad idea im not sure. If someone could explain this that would be quite helpful. Could i just use a resistor from the RX from the Arduino to the HC-05?