Löse das lineare Gleichungssystem.


`{(-3x,-,3y,-,z,+,9w,=,5),(6x,+,8y,-,2z,-,18w,=,-12),(-3x,-,3y,+,z,+,9w,=,7),(6x,+,6y,+,2z,-,21w,=,-16):}`

x =  
y =  
z =  
w =