Answer: 4 + (-n) and -n+4
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Explanation:
Adding a negative is the same as subtracting. For example, 10-7 = 10+(-7)
So that's why 4-n is the same as 4 + (-n)
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Then we go from 4 + (-n) to -n+4 because we can add two items in any order.
Example: 2+3 = 3+2 = 5
