Question 1173745
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1)


Start noticing that 10 = 1*10 = 2*5 = (-1)*(-10) = (-2)*(-5).


It gives you all possible values  b = 1   + 10     =   11;

                                      2   +  5     =    7;

                                     (-1) +  (-10) =  -11;

                                     (-2) +  (-5)  =   -7.
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