Answer:
5x - 14y + 16z + 2xy
Explanation:
Given expressions:
3x - 4y + 5z
2x - 7y
9z - 5y
-2xy - 2y -2z
Solution:
Sum of 3x - 4y + 5z
2x - 7y
9z - 5y
= 3x - 4y + 5z + 2x - 7y + 9z - 5y
= 3x + 2x - 4y - 7y -5y + 5z + 9z
= 5x - 16y + 14z
Subtract -2xy - 2y -2z
= 5x - 16y + 14z - ( -2xy - 2y -2z )
= 5x - 16y + 14z + 2xy + 2y + 2z
= 5x - 16y + 2y + 14z + 2z + 2xy
= 5x - 14y + 16z + 2xy