Write an algebraic expression for the given quantity. let x represent the unknown value.

one-half of a number

one-half is 1/2

"of" usually means multiply, as half of my money, etc.

So, what do you think?

To write an algebraic expression for one-half of a number, you can take the variable (let's say x) and multiply it by one-half. The expression would be:

(1/2) * x

This expression represents one-half of a number where x is the unknown value.