Question

Resolva o Sistema:
x + y + z = 3

2x − y + 2z = 5

x + 4y − 5z = 4

Answer 1

x + y + z = 3
2x - y + 2z = 5
x + 4y - 5z = 4
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x = 3 - y - z
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2(3 - y - z) - y + 2z = 5
6 - 2y - 2z - y + 2z = 5
-2y - y - 2z + 2z = 5 - 6
-3y + 0z = -1
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3 - y - z + 4y - 5z = 4
-y + 4y - z - 5z = 4 - 3
3y - 6z = 1
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-3y + 0z = -1
3y - 6z = 1

-6z = 0
z = 0/-6
z = 0

3y - 6.0 = 1
3y = 1
y = 1/3
y = 0,3


x = 3 - 0,3 - 0
x = 2,7