Answer:
x = 4; y = 3; z = 2
Step-by-step explanation:
3x + 2y + z = 20
x - 4y - z = -10
2x + y + 2z = 15
6x + 4y + 2z = 40
x - 4y - z = -10
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7x + z = 30
x - 4y - z = -10
8x + 4y + 8z = 60
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9x + 7z = 50
z = 30 - 7x
9x + 7(30 - 7x) = 50
9x + 210 - 49x = 50
-40x = -160
x = 4
z = 30 - 7(4)
z = 2
2x + y + 2z = 15
2(4) + y + 2(2) = 15
y = 3
x = 4; y = 3; z = 2
