0,4x-1,8=2+0,5x -2(x+8)+9=-3(x-8) 16/21x - 2,48=3/7x-1,18

1)-0,4x-1,8=2+0,5x

-0.4x-0,5x=2+1.8

-0.9x=3.8

x=-38/9

2)-2(x+8)+9=-3(x-8)

-2x-16+9=-3x+24

-2x-7=-3x+24

-2x+3x=24+7

x=31

3)16/21x - 2,48=3/7x-1,18

16/21x-62/25=3/7x-59/50

800x-2604=450x-1239

800x-450x=-1239+2604

350x=1365

x=39/10