Löse das lineare Gleichungssystem.


`{(30x,+,15y,-,9z,-,45w,=,-168),(12x,+,3y,-,6z,-,18w,=,-69),(6x,+,3y,-,3z,-,9w,=,-36),(-60x,-,30y,+,18z,+,89w,=,335):}`

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z =  
w =