Löse das lineare Gleichungssystem.


`{(6x,+,3y,-,2z,-,4w,=,-8),(-12x,-,8y,+,2z,+,8w,=,16),(12x,+,6y,-,2z,-,8w,=,-20),(-12x,-,6y,+,4z,+,7w,=,19):}`

x =  
y =  
z =  
w =