Answer:
(1, -1, 3)
Explanation:
The third equation says that z is equal to 3. So, we can replace this value on the second equation and solve for y as:
[tex]\begin{gathered} y+2z=5 \\ y+2(3)=5 \\ y+6=5 \\ y+6-6=5-6 \\ y=-1 \end{gathered}[/tex]Now, we can replace z by 3 and y by -1 on the first equation, so:
[tex]\begin{gathered} x-2y+2z=9 \\ x-2(-1)+2(3)=9 \\ x+2+6=9 \\ x+8=9 \\ x+8-8=9-8 \\ x=1 \end{gathered}[/tex]Therefore, the answer as an ordered triple is (x, y, z) = (1, -1, 3)