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2z - 31 = -9z + 24

can anyone tell me how to know if we must subtract or add? like we must write it as this when we solve it 2z - (- 9z) or 2z + -9z

2 Answers

5 votes
you move one of the equations to the other side and then combine like terms

User Syneryx
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2 votes
you would combine like terms so the answer would be -7z-7
User Aleksa
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