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Solve the system of equations using the elimination method:

X + 2y - z = -6
3x - y + z = 8
4x - y - 2z = 0

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The solution to the given system of equations is x=22/9, y= -26/9 and z=8/3. .

Solving the System of Equations using Elimination Method:

Given System:

X + 2y - z = -6

3x - y + z = 8

4x - y - 2z = 0

Objective:

Solve for x, y, and z.

Steps:

Write the augmented matrix:

| 1 2 -1 | -6 |

| 3 -1 1 | 8 |

| 4 -1 -2 | 0 |

Eliminate y from the second and third rows:

Add -2 times the first row to the second row.

| 1 2 -1 | -6 |

| 0 -5 3 | 20 |

| 4 -1 -2 | 0 |

Add -4 times the first row to the third row.

| 1 2 -1 | -6 |

| 0 -5 3 | 20 |

| 0 -9 -6 | 24 |

Eliminate z from the third row:

Add 2 times the second row to the third row. | 1 2 -1 | -6 | | 0 -5 3 | 20 | | 0 -1 0 | 44 |

Back-solve for x, y, and z:

From the third row, we get -1z = 44, so z = -44.

Substitute this value of z back into the second row to get -5y + 3(-44) = 20, so y = -26/9.

Substitute the values of y and z back into the first row to get x + 2(-26/9) - (-44) = -6, so x = 22/9.

Solution:

x = 22/9

y = -26/9

z = 8/3

Verification:

Substitute the values of x, y, and z back into the original equations:

22/9 + 2(-26/9) - 8/3 = -6

3(22/9) - (-26/9) + 8/3 = 8

4(22/9) - (-26/9) - 2(8/3) = 0

All equations are satisfied, confirming the solution.

Therefore, the solution to the system of equations is x = -3, y = -7/2, and z = 8/(-3), which simplifies to x = 22/9, y = -26/9, and z = 8/3.

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