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歡迎您訪問數(shù)學(xué)考題練習(xí)：已知，那么x-y的值是！

數(shù)學(xué)考題練習(xí)：已知，那么x-y的值是

更新時間：2024-01-12 16:31:28作者：貝語網(wǎng)校

已知，那么x-y的值是

A.1

B.-1

C.0

D.2

試題答案

B

試題解析

直接將二元一次方程組的方程（1）-（2），即可求得x-y的值．

解答：方程組

（1）-（2）得：x-y=-1．

故選B．

點評：本題要求同學(xué)們不僅熟悉代入法，更需要熟悉二元一次方程組的解法，解題時要根據(jù)方程組的特點進行有針對性的計算，注意整體思想的滲透．

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