Answer:
3x + 3
Explanation:
The given expression is 24x - 27 - 15 + 18 - 21x + 27.
To simplify this expression, we can combine like terms. Like terms are terms that have the same variable(s) and exponent(s). In this expression, we have two terms that have x: 24x and -21x. These terms can be combined by subtracting 21x from 24x to get 3x.
The other terms without any variables are -27, -15, 18, and 27. We can combine these terms by adding them together to get 3.
Therefore, the simplified expression is 3x + 3.