On mac OS X Yosemite, after installing it with brew it put it into
/usr/local/opt/openssl/bin/openssl
But kept getting an error "Linking keg-only openssl means you may end up linking against the insecure" when trying to link it
So I just linked it by supplying the full path like so
ln -s /usr/local/opt/openssl/bin/openssl /usr/local/bin/openssl
Now it's showing version OpenSSL 1.0.2o when I do "openssl version -a", I'm assuming it worked