The Associative Property of Addition states that the way in which numbers are grouped in an addition problem does not affect the sum. You can regroup the terms in the expression \(3x + (2y + z)\).
Using the Associative Property, you can rewrite it as:
\[ (3x + 2y) + z \]
So the expression \(3x + (2y + z)\) can be rewritten as \((3x + 2y) + z\).