Press Ctrl+Alt+T to open terminal, then get started with below steps:
1.) Check 32-bit or 64-bit by running this command in terminal
i686 will mean your system is 32-bit.
x86_64 will mean you’re on 64-bit.
2.) Download TeamViewer 8 via command:
3.) Install TeamViewer:
sudo dpkg -i teamviewer_linu*.deb
After that you can find TeamView from Unity Dash.