Question

14．二元一次方程組$\left\{\begin{array}{l}{x=3}\\{2x-y=8}\end{array}\right.$的解是$\left\{\begin{array}{l}{x=3}\\{y=-2}\end{array}\right.$．

Answer 1

分析 方程組利用代入消元法求出解即可．

解答 解：$\left\{\begin{array}{l}{x=3①}\\{2x-y=8②}\end{array}\right.$，
把①代入②得：6-y=8，
解得：y=-2，
則方程組的解為$\left\{\begin{array}{l}{x=3}\\{y=-2}\end{array}\right.$，
故答案為：$\left\{\begin{array}{l}{x=3}\\{y=-2}\end{array}\right.$

點(diǎn)評 此題考查了解二元一次方程組，熟練掌握運(yùn)算法則是解本題的關(guān)鍵．