题目内容
5.若$\left\{\begin{array}{l}{{a}_{1}x+{b}_{1}y={c}_{1}}\\{{a}_{2}x+{b}_{2}y={c}_{2}}\end{array}\right.$的解是$\left\{\begin{array}{l}{x=3}\\{y=4}\end{array}\right.$,则$\left\{\begin{array}{l}{3{a}_{1}(x-1)+{b}_{1}(y+3)={c}_{1}}\\{3{a}_{2}(x-1)+{b}_{2}(y+3)={c}_{2}}\end{array}\right.$的解是$\left\{\begin{array}{l}{x=4}\\{y=1}\end{array}\right.$.分析 根据已知得出方程组$\left\{\begin{array}{l}{x-1=3}\\{y+3=4}\end{array}\right.$,求出方程组的解即可.
解答 解:∵$\left\{\begin{array}{l}{{a}_{1}x+{b}_{1}y={c}_{1}}\\{{a}_{2}x+{b}_{2}y={c}_{2}}\end{array}\right.$的解是$\left\{\begin{array}{l}{x=3}\\{y=4}\end{array}\right.$,
∴$\left\{\begin{array}{l}{x-1=3}\\{y+3=4}\end{array}\right.$,
解得:$\left\{\begin{array}{l}{x=4}\\{y=1}\end{array}\right.$,
即$\left\{\begin{array}{l}{3{a}_{1}(x-1)+{b}_{1}(y+3)={c}_{1}}\\{3{a}_{2}(x-1)+{b}_{2}(y+3)={c}_{2}}\end{array}\right.$的解是$\left\{\begin{array}{l}{x=4}\\{y=1}\end{array}\right.$,
故答案为:$\left\{\begin{array}{l}{x=4}\\{y=1}\end{array}\right.$.
点评 本题考查了二元一次方程组的解和解二元一次方程组,能根据题意得出关于x、y的方程组是解此题的关键.
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