Question

Помогите, очень надо!

02d6a6cae060f73ecbb1cbf0dc236fd0.docx

Answer 1

1)2х+(11-4х)=21

2х+11-4х=21

-2х=21-11

-2х=10

х=10:(-2)

х=-5

2)а)7х+5х=25-13

12х=12

х=12/12

х=1

б)х+10-20х=29

-19х=29-10

-19х=19

х=19/-19

х=-1