How to retrieve all the employees whose firstname starts with letter R?

See more:

SQL

SQL-Server

Ihave a table named tbl_emp which contains (firstname,lastname,birthdate,civilstatus,religion). How can I get all the employees whose first name starts with letter R without using LIKE 'R%' and substring. Is there another way?

What I have tried:

SELECT firstname
FROM tbl_emp
WHERE firstname LIKE '5%'

and the other one uses substring.