8х-(7х-142)=51
(6-2х)+4=-5х+5,5

8х-(7х-142)=51

8х-7х+142=51

8х-7х=51-142

Х=-91

(6-2х)+4=-5х+5,5

6-2х+4=-5х+5,5

5х-2х=5,5-4-6

3х=-4,5

Х=-4,5:3

Х=-1,5

8х-(7х-142)=518х-7х+142=51х=51-142х=-91Ответ: х=-91(6-2х)+4=-5х+5,56-2х+4=-5х+5,53х=5,5-6-43х=-4,5х=-1,5Ответ: х=-1,5