4(x一y)十5(x一y)一11(x一y)=-2(x-y)=2(y-x)
①x=3,y=1
2(y-x)=2(1-3)=-4
②x=0,y=-2
2(y-x)=2(-2-0)=-4
③x=-0·5,y=-2·5
2(y-x)=2(-2.5+0.5)=-4
4(x一y)十5(x一y)一11(x一y)=-2(x-y)=2(y-x)
①x=3,y=1
2(y-x)=2(1-3)=-4
②x=0,y=-2
2(y-x)=2(-2-0)=-4
③x=-0·5,y=-2·5
2(y-x)=2(-2.5+0.5)=-4