To simplify the expression \( 3x + (x + 2) \) using the Associative Property, we can group the terms in different ways. The Associative Property states that the way in which numbers are grouped in addition does not affect their sum.
Starting with the expression:
\[ 3x + (x + 2) \]
We can remove the parentheses without changing the value of the expression:
\[ 3x + x + 2 \]
Now, we can combine like terms. The like terms here are \( 3x \) and \( x \):
\[ 3x + x = 4x \]
So, we rewrite the expression as:
\[ 4x + 2 \]
Thus, the simplest equivalent form of the expression \( 3x + (x + 2) \) is:
\[ 4x + 2 \]