(Show your complete solution.)

I. A. Find the sum.


1. (−6 − 3) + (3 − 9)

Solution=

2. (3
2 + 5 − 9) + (−3 + 4)

Solution=

3. (4
2 + 3 + 6) + (6
2 + 3 − 7)

Solution=

4. (3
2 + 6 + 8) + (2
2 − 2
− 11)
Solution=​