Answers:
1. d
2. c
3. b
4. a
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Explanation:
For problem 1, subtracting a negative is the same as adding a positive. The two negatives cancel out
In problem 2, we can add a negative to mean we're subtracting. One way to think of it is like adding on debt to your bank balance.
Problem 3 is similar to problem 2. The first term -17 isn't changed.
Problem 4 is similar to problem 1. The only difference is that the 17 is negative this time around.
