Answer:
-4x + 16y + 3xy
Step-by-step explanation:
The sum of 3x + 4y - 3xy and 5x + 3y - 2xy is 8x + 7y - 5xy.
The sum of 2x + y - 3xy and 10x - 9y - 8xy is 12x - 8y - 11xy.
Subtract the sum of the second pair from the first pair by changing the sign of the subtrahend. The result is -4x + 16y + 3xy
