[–] 3dk 0 points 1 point 1 point (+1|-0) ago (edited ago)
Did you use Ubuntu software manager or the installer from steam? You should use your distro's package manager.
You might be missing some dependencies. Find the steam binary, open a terminal in that directory and type: ldd ./steam to see which libs are missing. Then find the right packages to install those libs.
Search around Askubuntu. They probably know what to do.