Explanation
Given the equations;
[tex]\begin{bmatrix}6x-6y-2z=3-----i \\ -2x+5y-z=3----ii \\ 5x+y-5z=-4----iii\end{bmatrix}[/tex]
We are asked to find its solution.
First, we isolate x from the first equation
[tex]\begin{gathered} 6x-6y-2z=3 \\ 6x=3+6y+2z \\ x=\frac{3+6y+2z}{6} \end{gathered}[/tex]
Substitute x in the remaining equations
[tex]\begin{bmatrix}-2\cdot\frac{3+6y+2z}{6}+5y-z=3 \\ 5\cdot\frac{3+6y+2z}{6}+y-5z=-4\end{bmatrix}=\begin{bmatrix}\frac{9y-5z-3}{3}=3----iv \\ \frac{36y-20z+15}{6}=-----v\end{bmatrix}[/tex]
From equation iv above, we will isolate y
[tex]\begin{gathered} \frac{9y-5z-3}{3}=3 \\ 9y-5z-3=9 \\ 9y=9+5z+3 \\ y=\frac{12+5z}{9} \end{gathered}[/tex]
Substitute y in equation v
[tex]\begin{gathered} \begin{bmatrix}\frac{36\cdot\frac{5z+12}{9}-20z+15}{6}=-4\end{bmatrix}\Rightarrow\frac{20z+48-20z+15}{6}=-4 \\ \Rightarrow\frac{63}{6}=-4 \\ \Rightarrow\frac{21}{2}=-4 \\ \frac{21}{2}=-4\: \mathrm{\: is\: false,\: therefore\: the\: system\: of\: equations\: has\: no\: solution} \end{gathered}[/tex]
Answer: No solution