Solve the system of equations using substitution. Write your answer as an ordered triple in the form (x, y, z). X+ y + z = 2
4x + 5y + z = 12
2x = -4

  (x, y, z) = (-2, 4, 0)

Step-by-step explanation:

Solving the last equation first, we have ...

  2x = -4

  x = -2 . . . . . divide by 2

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Putting this in the first equation, we can write an expression for z:

  -2 +y +z = 2

  z = 4 -y . . . . . . . add 2-y

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Putting this in the second equation, we have ...

  4(-2) +5y +(4 -y) = 12

  -4 +4y = 12

  -1 + y = 3 . . . . . divide by 4

  y = 4 . . . . . . . . add 1

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Substituting this into the equation for z, we have ...

  z = 4 - 4 = 0

The solution is (x, y, z) = (-2, 4, 0).