record from system audio AND mic

I’m trying to record a podcast, and need to record system volume (other people in the podcast) AND the mic (myself).

I’m running Linux (Cruton on a Chromebook). I know very little about Linux, I know it’s “Trusty” if that matters.

I have Audacity installed and PulseAudio. I can get it to record system audio, and I can get it to record mic audio, but I can’t get it to record both at the same time.

I can provide screenshots of whatever you want to see on my system.

I did a search, and the only topic I found suggested using a hardware mixer. Is there no way to do it without extra hardware?

You forgot Skype. You want that, too, right?