Answer
$11+3x$
Work Step by Step
We start with the given expression: $(2+3x)+9$
The commutative property of addition states that changing the order of the addends does not affect the sum.
We use this property to rearrange the addends: $9+(2+3x)$
The associative property of addition states that changing the grouping of the addends does not affect the sum.
We use this property to group the addends differently: $(9+2)+3x$
We use the order of operations to simplify.
We simplify inside the parentheses: $11+3x$