Question

3．方程y=1-x與3x+2y=5的公共解是（　�。�

• A． $\left\{\begin{array}{l}{x=3}\\{y=2}\end{array}\right.$
• B． $\left\{\begin{array}{l}{x=-3}\\{y=4}\end{array}\right.$
• C． $\left\{\begin{array}{l}{x=3}\\{y=-2}\end{array}\right.$
• D． $\left\{\begin{array}{l}{x=-3}\\{y=-2}\end{array}\right.$

Answer 1

分析 先畫(huà)出函數(shù)y=1-x和函數(shù)3x+2y=5的圖象，確定它們的交點(diǎn)坐標(biāo)，然后根據(jù)函數(shù)圖象交點(diǎn)坐標(biāo)為兩函數(shù)解析式組成的方程組的解即可得到答案．

解答 解：如圖，所以方程y=1-x與3x+2y=5的公共解為$\left\{\begin{array}{l}{x=3}\\{y=-2}\end{array}\right.$．

故選C．

點(diǎn)評(píng) 本題考查了一次函數(shù)與二元一次方程（組）：函數(shù)圖象交點(diǎn)坐標(biāo)為兩函數(shù)解析式組成的方程組的解．