Câu hỏi của Thị lan Trần

\(\left\{{}\begin{matrix}x_1+x_2=-4m-1\\x_2-x_1=17\end{matrix}\right.\)\(\Leftrightarrow\left\{{}\begin{matrix}x_1+x_1+17=-4m-1\\x_2=x_1+17\end{matrix}\right.\)\(\Leftrightarrow\left\{{}\begin{matrix}2x_1=-4m-18\\x_2=x_1+17\end{matrix}\right.\)\(\Leftrightarrow\left\{{}\begin{matrix}x_1=-2m-9\\x_2=-2m+8\end{matrix}\right.\)Câu trả lời: \(\left\{{}\begin{matrix}x_1+x_2=-4m-1\\x_2-x_1=17\end{matrix}\right.\)\(\Leftrightarrow\left\{{}\begin{matrix}x_1+x_1+17=-4m-1\\x_2=x_1+17\end{matrix}\right.\)\(\Leftrightarrow\left\{{}\begin{matrix}2x_1=-4m-18\\x_2=x_1+17\end{matrix}\right.\)\(\Leftrightarrow\left\{{}\begin{matrix}x_1=-2m-9\\x_2=-2m+8\end{matrix}\right.\)