Question

已知集合M＝{(x, y)| x+ y ="3}," N ={(x,y)|x－ y =5}則集合M∩N＝(  )

A．x =" 4," y =－1

B．{(4,－1)}

C．(4,－1)

D．{4 ,－1}

Answer 1

B.

由，解之得,所以.故選B。