From: Lisa Phipps
To: Teacher2Teacher Public Discussion
My daughter is learning subtraction of intergers and it's been years since I've done them. When do you change the sign for the second number? and why? She has -5 + +7=. he teacher told her she needed to change it to -5 - -7=. Why do you change it? On the first one I would get +2 and on the second one I would get -2. Is this correct?
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