To simplify the expression \( 4x + 8x \) using the properties of operations, you can combine like terms. Both terms contain the variable \( x \).
Here's how to do it step-by-step:
- Identify the coefficients: The coefficients are 4 and 8.
- Add the coefficients together: \( 4 + 8 = 12 \).
- Multiply the sum of the coefficients by the variable \( x \): \( 12x \).
Thus, the simplified expression is:
\[ 12x \]