Respuesta :

the answer is (-8) because x=4, y=-6, z=11

These consists of more than 1 equation with unknown variables. The value that is not a solution in (x,y, z)is -8

System of equations

These consists of more than 1 equation with unknown variables. Given the set of equations

x+y+z=9

x-y-z=-1

x-y+z= 21

Add 1 and 2

2x = 9 - 1

2x = 8

x = 4

Subtract 2 and 3

-2z = -22

z = 11

Determine the value of y

x +y + x = 9

4 + y + 11 = 9

y = 9 - 15

y = -6

Hence the value that is not a solution in (x,y, z)is -8

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