The problem asks to represent the following sentence as an algebraic expression: "A number is subtracted from 2", where "a number" is represented by the letter x.

When something is subtracted from another, it implies the format: 2 - x.

Thus, the algebraic expression for this sentence is:

$2 - x$

Would you like further details or explanations? Here are 5 related questions you might find helpful:

1. How do you interpret different phrases when writing algebraic expressions?
2. How would you write the expression for "2 more than a number"?
3. What is the expression for "a number subtracted from 10"?
4. How can you represent "3 times a number is subtracted from 8"?
5. How do you combine like terms in algebraic expressions?

Tip: In algebraic expressions, the order in subtraction matters—always pay attention to which number is being subtracted from which.