Answer:
8x-8z
Explanation:
6x-3y-z+2x+3y-7z this equation goes to every step below.
since there are 2 opposites, add up to zero, remove them from the expression
-> 6x-z+2x-7z. (-3y. +3y)
collect like terms.
-> 8x-z-7z. (6x. +2x)
collect like terms.
-> 8x-8z