Question

tìm x bt

Answer 1

`25-(30+x)=x-(27-8)`

`<=> 25 - 30 - x = x - 27 + 8`

`<=> -x - x = 8 - 27 - 25 + 30`

`<=>-2x = -14`

`<=> x = (-14) : (-2)`

`<=> x = 7`

`15-(13+x)=x-(23-17)`

`⇔15-13-x=x-23+17`

`⇔2x-6=2`

`<=>2x=8`

`x=4`

`-(x-6+85)=(x+51)-54`

`⇔ -x-x = 51-54+85-6`

`⇔-2x = 76`

`⇔-x =38`

`⇔x=-38`