I dont mean to sound like a knob, but IIRC fedora doesnt enable sudo by default.
If 16pide's "sudo your-command" gives you an error, you may need to
and uncomment the "%wheel ALL=(ALL) ALL" line, this will enable sudo, then:
# usermod -a -G wheel $username
which will add $username to the "wheel" group, which is specified by visudo
alternatively to sudo, you can use "su -c" to execute a command as root like so:
$ su -c 'shutdown -r now'