Answers

2016-06-29T20:46:18+08:00
1 - -5 = 6 
copy change change.  so it will be 1 + 6 
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2016-06-29T20:59:09+08:00
1-(-5)
will be
1+5
because there's 2 negative symb.
so the answer is 6 
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