Final answer:
The Commutative property of addition is the principle that represents the given equation. It demonstrates that the order in which numbers are added doesn’t change the sum.
Step-by-step explanation:
The property that is illustrated by the given equation, 1 + (-8) =(-8) + 1, is the Commutative property of addition. This property states that the order in which numbers are added does not change the sum. For example, if you have two numbers, a and b, the sum of a + b would be the same as b + a which aligns with the equation given in the question.
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