Question

14．若方程组$\left\{\begin{array}{l}{2a-3b=m}\\{3a+5b=n}\end{array}\right.$的解是$\left\{\begin{array}{l}{a=8.3}\\{b=1.2}\end{array}\right.$，则方程组$\left\{\begin{array}{l}{2（x-1）-3（y+2）=m}\\{3（x-1）+5（y+2）=n}\end{array}\right.$的解是（　　）

• A． $\left\{\begin{array}{l}{x=9.3}\\{y=-0.8}\end{array}\right.$
• B． $\left\{\begin{array}{l}{x=8.3}\\{y=1.2}\end{array}\right.$
• C． $\left\{\begin{array}{l}{x=7.3}\\{y=3.2}\end{array}\right.$
• D． $\left\{\begin{array}{l}{x=10.3}\\{y=0.2}\end{array}\right.$

Answer 1

分析 仿照已知方程组的解，确定出所求方程组的解即可．

解答 解：∵方程组$\left\{\begin{array}{l}{2a-3b=m}\\{3a+5b=n}\end{array}\right.$的解是$\left\{\begin{array}{l}{a=8.3}\\{b=1.2}\end{array}\right.$，
∴方程组$\left\{\begin{array}{l}{2（x-1）-3（y+2）=m}\\{3（x-1）+5（y+2）=n}\end{array}\right.$的解为$\left\{\begin{array}{l}{x-1=8.3}\\{y+2=1.2}\end{array}\right.$，即$\left\{\begin{array}{l}{x=9.3}\\{y=-0.8}\end{array}\right.$，
故选A

点评 此题考查了二元一次方程组的解，方程组的解即为能使方程组中两方程都成立的未知数的值．