Answers

2015-07-21T17:56:47+08:00
-10.....................................................................
                                   
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2015-07-21T18:25:16+08:00
You said ...from positive 7.. so it looks like this .. 7 - (-3) .. so the answer is 10..

but if it is ...by positive 7, it would look like this.. -3-7.. = -10
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