ok, so my problem was that I tried to install the package with yum which is the primary tool for getting, installing, deleting, querying, and managing Red Hat Enterprise Linux RPM software packages from official Red Hat software repositories, as well as other third-party repositories.
But I'm using ubuntu and The usual way to install packages on the command line in Ubuntu is with apt-get. so the right command was:
sudo apt-get install libstdc++.i686