Löse das lineare Gleichungssystem.


`{(-6x,-,3y,-,2z,+,6w,=,5),(4x,,,+,4z,-,4w,=,-20),(2x,+,y,+,2z,-,2w,=,-7),(18x,+,9y,+,6z,-,20w,=,-19):}`

x =  
y =  
z =  
w =