You cannot do this and get the right behavior.
RVM operates in its own directory when operating as a single-user sandbox. Any Ruby that it controls will exist in your ~/.rvm .
Anything outside the RVM control will be considered a system parameter, and you will need to decide whether it is regular Ruby installed in /usr/bin or /usr/local/bin or in /opt or elsewhere.
In my opinion, you should let RVM manage Ruby installations. It is very sleek and quickly became the preferred way to manage Ruby development environments on Linux and Mac OS.
You can try to create aliases from the Cellar folder in the appropriate place in ~/.rvm , but RVM changes some things during the installation process, for example gem , which would not be done in the folder installed in Homebrew, and would lead to RVM support -gem will break for this version of Ruby.