The Associative Property say that it doesn't matter how we group the numbers (i.e. which we calculate first) when we add
(a + b) + c = a + (b + c)
The Commutative Property say we can swap numbers over and still get the same answer when we add
a + b = b + a
The Distributive Property:
a(b + c) = ab + ac
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-3a + 4b + 5a + (-7b) = -3a + 5a + 4b + (-7b)
Answer: the commutative property