Question

Long addition for integers

Answer 1

-9 + 6 + (-7) +3=
-9 +6 = -3
-3 + (-7)= -10
-10 +3= -7

Answer 2

-4 + 9 = 5

-81 + -56 = -137

40 + 23 = 63

positive + negative (convert it to subtraction the sign changes when it depends on the higher number)

negative + negative = negative

positive + positive = positive