Answer:
x - 6y + 10z
Step-by-step explanation:
7x + 3y - 5z - (8x - 3y + 5z)
= 7x + 3y - 5z - 8x + 3y - 5z
= 7x - 8x + 3y + 3y - 5z - 5z
= - x + 6y - 10z
OR
= -(- x + 6y - 10z)
= x - 6y + 10z
