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Answer:
z = 4
y = -1
x = 2
Step-by-step explanation:
x - y = 3
Therefore => x = 3 + y
y + 2z =7
Therefore => y= 7 - 2z
We have the equation :
2x + 3y + 4z = 17
2(3 + y) + 3(7 - 2z) + 4z = 17
6 + 2y + 21 - 6z +4z = 17
2(7 -2z) - 2z + 27 = 17
14 - 4z - 2z + 27 = 17
-6z + 41 = 17
-6z = -24
z = 4