Verified answer

1)(x-12)*2=x*2-24

2)x*4-(x*2-24)=x*4-x*2+24

3)x*2-x*4=2*x

2*x+24=0

Verified answer

 х4=(х-12)2

4х=2х-24

4х-2х=-24

2х=-24

х=-24:2

х=-12

Проверка:

-12*4=(-12-12)2

-48=-24*2

-48=-48