Answer:
-3
Step-by-step explanation:
Note the right side of the equation. There is a negative sign outside of the parenthesis. Distribute the negative sign to all terms within the parenthesis:
x + 3 = - (-x + __)
x + 3 = x - ___
Note:
1) When multiplying a negative and positive together, the answer will be negative
2) When multiplying a negative and negative together, the answer will be positive:
x + 3 = x - ___
Note the equal sign, this means that the two side of the equation must equal. This means that the only answer choice is -3:
x + 3 = x - (-3)
x + 3 = x + 3 (True)
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