Answer: 54-x
Step-by-step explanation:
1. We define the variable which is x or n (whichever you choose)
2. We write the algebraic expression that models the following problem:
the difference of 54 and a number.
3. We end up with our answer: 54-n OR 54-x
(Variable doesn't matter but most people use x when they don't have a named variable)
Hope this helps!!