Step-by-step explanation:
Start filling in from the bottom, left to right
Row 2 from bottom:
- -2x + 3
- 3 + (-5) = -2
- -5 + 7y = 7y - 5
- 7y + 1
Row 3 from bottom:
- 2x + (-2x) + 3 = 3
- -2x + 3 + (-2) = -2x + 1
- -2 + 7y - 5 = 7y - 7
Row 4 from bottom:
- 3 + (-2x) + 1 = -2x + 4
- 7y - 7 - 5 + 15y = 22y - 12
Row 5 from bottom:
- -2x + 4 -2x - 6 + 7y = -4x + 7y - 2
- -2x - 6 + 7y + 22y - 12 = -2x + 29y - 18
Top row:
- -4x + 7y - 2 - 2x + 29y - 18 = -6x + 36y - 20
