So here is my stands on this:
For main scanning and everything like that, use avast, but if you really need a second opinion scan to be sure that you have no malware like once a few months or so, you can use malware bites, it's a good second opinion scanner.
And as for your question if they can work together: Well as I've said malwarebites is a second opinion scanner so you just run it whenever you want, however yes they should work with no problem.
