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Description:Added 3x3 system solving example
# Example of solving a 3-by-3 system of linear equations by row-reducing the augmented matrixPut content here.## Example: Solving a 3-by-3 System by Row Reduction ⏎ Solve: ``` 2x + y - z = 8 -3x - y + 2z = -11 -2x + y + 2z = -3 ``` ⏎ **Step 1:** Write augmented matrix ``` [ 2 1 -1 | 8] [-3 -1 2 |-11] [-2 1 2 | -3] ``` ⏎ **Step 2:** R₁ → R₁/2 ``` [ 1 0.5 -0.5 | 4] [-3 -1 2 |-11] [-2 1 2 | -3] ``` ⏎ **Step 3:** R₂ → R₂ + 3R₁, R₃ → R₃ + 2R₁ ``` [ 1 0.5 -0.5 | 4 ] [ 0 0.5 0.5 | 1 ] [ 0 2 1 | 5 ] ``` ⏎ **Step 4:** R₂ → 2R₂ ``` [ 1 0.5 -0.5 | 4 ] [ 0 1 1 | 2 ] [ 0 2 1 | 5 ] ``` ⏎ **Step 5:** R₃ → R₃ - 2R₂ ``` [ 1 0.5 -0.5 | 4 ] [ 0 1 1 | 2 ] [ 0 0 -1 | 1 ] ``` ⏎ **Step 6:** R₃ → -R₃, then back-substitute: z = -1, y = 2 - (-1) = 3, x = 4 - 0.5(3) + 0.5(-1) = 2 ⏎ **Solution:** x = 2, y = 3, z = -1 # Parents * Using matrices to solve linear systems * Using matrices to solve linear systems * Using matrices to solve linear systems
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