It's hard to say because you did not show any parentheses. That means assumptions must be made about the actual operations. I'm going to assume this (only you know if my assumptions are right)
You have to use pemdas to figure this equation out. (ask if you dont know) So, you do division first. 12 / 4 = 3. And now we do 3*3, which is 9. and 57 - 9 = 48.
