I tutor with Wyzant. They charge me 30% of every hour tutored in fees to use their service to work with students. Can I write off this fee as a business expense?

I tutor with Wyzant.  They don't send out W2's because we're considered independent contractors; we get a 1099 instead.  However, they take a significant portion of what tutors earn in fees (30% of every hour tutored).  Can I write these fees off as a business expense since I'm using their website as a service to find and work with students?