Question

which property of real numbers is shown?
$3+((-5)+6)=(3+(-5))+6$
associative property of addition
commutative property of addition
commutative property of multiplication
identity property of multiplication

Explanation:

The equation rearranges the grouping of addends without changing the order of the numbers, which matches the definition of the associative property of addition. This property states that for any real numbers $a$, $b$, $c$, $a+(b+c)=(a+b)+c$.

Answer:

associative property of addition