Answers

2016-04-07T22:58:37+05:30
–7 – (–3)
= -7+3              {minus and minus is plus}
=  -4                 {minus and plus is minus ,as the minus symbol has a                                      greater value ,put minus infront of the ans}

he must have done -7-3 instead of doing -7+3

1 5 1