Mysqladmin -u root create asterisk with password?

i’m installing asterisk and freepbx on a webserver with centos, mysql, apache, php and plesk just installed.

I’m following this guide:

I arrived where say:
Configure Asterisk database in MYSQL.
If i try to send command “mysqladmin -u root create asterisk” i receive this error message:

mysqladmin: connect to server at ‘localhost’ failed
error: ‘Access denied for user ‘admin48494833’@‘localhost’ (using password: NO)’

How i can continue?
Thank you