How to perform an update containing a sub query on an Eloquent Relationship in laravel 5

I am new to laravel. I'm working on this laravel 5 app but got stuck on trying to perform a query like below.

update applications 
set application_status = 'sa'
where id in (select application_id from application_cart where cart_id = 12);

Appreciate help on how to translate this query.

via Chebli Mohamed