证明:
(m-1)x+(2m-1)y=m-5
mx-x+2my-y=m-5
m(x+2y-1)=x+y-5
当x+2y-1=0时,不管m为何实数,都有m(x+2y-1)=0,即与m无关
所以x+y-5=0
解x+y-5=0和x+2y-1=0,得x=9,y=-4
所以直线必过(9,-4)
证明:
(m-1)x+(2m-1)y=m-5
mx-x+2my-y=m-5
m(x+2y-1)=x+y-5
当x+2y-1=0时,不管m为何实数,都有m(x+2y-1)=0,即与m无关
所以x+y-5=0
解x+y-5=0和x+2y-1=0,得x=9,y=-4
所以直线必过(9,-4)