Question

-( x - 2y) - [ { 3x - 2 ( 2y - z ) } - { 4x - ( 3y - 2z ) } ]

Answer 1

 -( x - 2y) - [ { 3x - 2 ( 2y - z ) } - { 4x - ( 3y - 2z ) } ]
= -x+2y-3x-4y-z-4y+3y-2z
= -x-3x+2y-4y-4y+3y-z-2z
= 4x-2y+7y+3z