①人大是我国的立法机关              ②我国人民当家作主具有真实性

③人民代表大会是我国的根本政治制度  ④全国人大坚持科学立法、民主立法

已知二元一次方程组的增广矩阵为$\left(\begin{array}{c}\begin{array}{ccc}2& 1& 8\end{array}\\ \begin{array}{ccc}0& 1& 2\end{array}\end{array}\right)$，则此方程组的解集为____ ．

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                                                                                                       月夜忆舍弟
                                                                                                            杜甫
                                                                                            戍鼓断人行，边秋一雁声。
                                                                                            露从今夜白，月是故乡明。
                                                                                            有弟皆分散，无家问死生。
                                                                                            寄书长不达，况乃未休兵。