若2x-y=8,则6-2x+y等于多少?

若2x-y=8,则6-2x+y等于多少?
若2x-y=8,则6-2x+y等于多少?

若2x-y=8,则6-2x+y等于多少?
2x-y=8
两边乘-1
-2x+y=-8
6-2x+y=6-8=-2

6-2x+y
=6-(2x-y)
=6-8
=-2

2x-y=8
y=2x-8
6-2x+y=6-2x+(2x-8)=6-8=-2

-2

因为2x-y=8，所以先不看6，-2x+y就是2x-y的相反数，则-2x+y=-8，得：6-8=-2