Answer
$(2,-3,-1)$
Work Step by Step
1. Eliminate $y$, multiply 2 to the first equation and add the result to the second to get $8x+9z=7$
2. Eliminate $y$, multiply -3 to the first equation and add the result to the third to get $-8x-4z=-12$ or $2x+z=3$
3. Eliminate $x$, multiply -4 to the equation in step-2 and add the result in step-1 to get $5z-5$, thus $z=-1$
4. Back substitute to get $x=2$ and $y=-3$, thus the solution $(2,-3,-1)$
