Solve the linear system LaTeX: \displaystyle \begin{cases} 2 x - 9 y + 6 z = -119 \\ 9 x + 7 y + z = 126 \\ - 8 x + 8 y - 3 z = 35 \\ \end{cases}

The Solution is LaTeX: \displaystyle (8, 9, -9) .