Open your Bashrc file
sudo gedit .bashrc
To demonstrate an example mutliple Environment Variable
FIRST_VARIABLE=<full path>
SECOND_VARIABLE=<full path>
PATH=$PATH:$FIRST_VARIABLE/$SECOND_VARIABLE
export PATH
Lastly save the file and confirm by doing an Echo.
echo $FIRST_VARIABLE
echo $SECOND_VARIABLE
If you see the fullpath it means you are doing it right.