Question

Which algebraic expression represents the difference of 54 and s number

Answer 1

$\huge\boxed{54-x}$

I'm assuming you meant "the difference between 54 and a number". We'll use $x$ to represent the number.

The word "difference" means that we will use subtraction, making the answer...

$\boxed{54-x}$

Answer 2

the other guy is correct