Rewriting the expression 15x+9 as 9+ 15x is an example of the property of

Rewriting the expression 15x+9 as 9+ 15x is an example of the commutative property of addition

The commutative property of addition states that when two numbers are being added, their order can be changed without affecting the sum.

To “commute” means to move around or travel.  

According to the commutative property of addition, changing the order of the numbers we are adding, does not change the sum

When two numbers are added, the sum is the same regardless of the order of the addends. For example 4 + 2 = 2 + 4

For addition, the rule is a + b = b + a

Here in the problem 15x + 9 is equivalent to 9 + 15x

Hence, rewriting the expression 15x+9 as 9+ 15x is an example of the commutative property of addition

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