Question

Giải giúp mình theo phương pháp GAUSS ạ:

Answer 1

\(\Leftrightarrow\left\{{}\begin{matrix}2x+y+2z=200\\8y+5z=470\\y-2z=-20\end{matrix}\right.\) ((2)=3.(2)-5.(3); (3)=2.(3)-3.(1))

\(\Leftrightarrow\left\{{}\begin{matrix}2x+y+2z=200\\8y+5z=470\\-21z=-630\end{matrix}\right.\) ((3)=(3)-8.(2))

\(\Leftrightarrow\left\{{}\begin{matrix}2x+y+2.30=200\\8y+5.30=470\\z=30\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x=50\\y=40\\z=30\end{matrix}\right.\)