Question

6．若方程組$\left\{\begin{array}{l}{x-2y=3}\\{3x+4y=5}\end{array}\right.$的解是$\left\{\begin{array}{l}{x=2.2}\\{y=-0.4}\end{array}\right.$，則方程組$\left\{\begin{array}{l}{（a+2012）-2（b-2013）=3}\\{3（a+2012）+4（b-2013）=5}\end{array}\right.$的解為（　　）

• A． $\left\{\begin{array}{l}{a=2.2}\\{b=-0.4}\end{array}\right.$
• B． $\left\{\begin{array}{l}{a=2014.2}\\{b=2012.6}\end{array}\right.$
• C． $\left\{\begin{array}{l}{a=-2009.8}\\{b=2012.6}\end{array}\right.$
• D． $\left\{\begin{array}{l}{a=2014.2}\\{b=2013.4}\end{array}\right.$

Answer 1

分析 根據(jù)已知方程組的解，確定出所求方程組的解即可．

解答 解：由題意得：所求方程組的解為$\left\{\begin{array}{l}{a+2012=2.2}\\{b-2013=-0.4}\end{array}\right.$，
解得：$\left\{\begin{array}{l}{a=-2009.8}\\{b=2012.6}\end{array}\right.$，
故選C

點評 此題考查了二元一次方程組的解，弄清已知方程組與所求方程組的共同特征是解本題的關(guān)鍵．