I've only ever installed MySQL separately but it installs to C:\MySQL as standard.
The EXEs are in the 'bin' directory off that. You'll need to add them to your path statement if you want to run it from any location but bin.
The command (in the command line) should be something like:
Set path=%PATH%;c:\mysql\bin;c:\mysql
Assuming the MySQL path is right. You should probably alter your config.sys file (I think it is, there's a second one too) to make it permanent.