Let's fill in the blanks:
Add: (-8) + (-5)
- Start at 0.
- Plot -8 by moving 8 units to the left.
- Add -5 by moving 5 units to the left.
- (-8) + (-5) = -13
Add: 6 + (-2)
- Start at 0.
- Plot 6 by moving 6 units to the right.
- Add -2 by moving 2 units to the left.
- 6 + (-2) = 4