(5y+3x-15z²)-(12y+7x+z²)我要全过程不要去括号后写答案,我还要去括号后的过程,然后在写答案.

(5y+3x-15z²)-(12y+7x+z²)我要全过程不要去括号后写答案,我还要去括号后的过程,然后在写答案.
(5y+3x-15z²)-(12y+7x+z²)我要全过程不要去括号后写答案,我还要去括号后的过程,然后在写答案.

(5y+3x-15z²)-(12y+7x+z²)我要全过程不要去括号后写答案,我还要去括号后的过程,然后在写答案.
(5y+3x-15z²)-(12y+7x+z²)
=5y+3x-15z²-12y-7x-z²
=-7y-4x-16z²

(5y+3x-15z²)-(12y+7x+z²)
=5y+3x-15z²-12y-7x-z²
=(5y-7y)+(3x-7x)-(15z²+z²)
=-2y-4x-16z²