-7x = -12
x = -12/-7
х=12/7
х=1 5/7
48x = -16
х=-16/48
х=-1/3
5x+9 = 0
5х=-9
х=-1 4/5
5x+4 = x-12
5х-х=-12-4
4х=-16
х=-4
4x-(6-x) = 13
4х-6+х=13
5х=19
х=19/5
х=3 4/5
Вот ответ.AB,AC,AD,CD,CB,DB
2,56×0,44×2,25/3,2×0,12×0,6=11
1) 2,56 × 0,44 = 1,1264
2) 1,1264 × 2,25 = 2,5344
3) 3,2 × 0,12 = 0,384
4) 0,384 × 0,6 = 0,2304
5) 2,5344 : 0,2304 = 11
ответ: 11
5,04:(104,2-x)=1,2
104,2-x=5,04:1,2
104,2-x=4,2
x=104,2-4,2
x=100
====================