Rules for removing brackets in primary school mathematics in Beijing curriculum reform edition

The rules for removing brackets are the same everywhere.

1. Parentheses are preceded by a "+". After removing the brackets and the "+"sign in front of them, the symbol of the original brackets remains unchanged.

There is a "-"before the brackets. After removing the brackets and the preceding "-"sign, the symbol of the original brackets will change. (changed to the opposite symbol)

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Exactly the same. What do you mean?

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