The system of equations are

$\"\"$

Write the equations into matrix form $\"\"$ .

$\"\"$ is coefficient matrix, $\"\"$ is variable matrix and $\"\"$ is constant matrix.

$\"\"$

Solve the equations in Gaussian elimination method.

The augmented matrix is $\"\"$ .

$\"\"$

$\"\"$ are represents first row and second row.

Eliminate second row and first coloumn.

$\"\"$