Question

resolva o sistema

2x + 3y - z = 0
x - 2y + z = 5
-x +y +z = -2

Answer 1

2x + 3y - z = 0
x - 2y + z = 5
-x + y + z = -2
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x = 5 + 2y - z

2x + 3y - z = 0
2.(5 + 2y - z) + 3y - z = 0
10 + 4y - 2z + 3y - z = 0
7y - 3z = -10

-x + y + z = -2
-5 - 2y + z + y + z = -2
-2y + y + z + z = -2 + 5
-y + 2z = 3


7y - 3z = -10
-y + 2z = 3 . (7)
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7y - 3z = -10
-7y + 14z = 21
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11z = 11
z = 11/11
z = 1

7y - 3z = -10
7y - 3.1 = -10
7y - 3 = -10
7y = -10 + 3
7y = -7
y = -7/7
y = -1


x = 5 + 2y - z
x = 5 + 2.(-1) - 1
x = 5 - 2 - 1
x = 5 - 3
x = 2


S={ 2, -1, 1 }



★Espero ter ajudado!! tmj