Question

All of the following could be rewritten as an addition problem of two integers with the same sign except _____.

-9 - (-12)
-9 - 12
-12 - 9
12 - (-9)

Answer 1

Answer is - 9 + 12 because they have different signs in front of each integer. (if that is what the question means)

Explanation:

Negative sign x negative sign = positive sign

-9 - (-12) = -9 + 12

-9 - 12

-12 - 9 = -9 - 12

12 - (-9) = 12 + 9 = 9 + 12