6-3(2x-4)= -8x+4
6-6x+12= -8x+4
18-6x=-8x+4
-6x+8x=4-18
2x= -14
x= -14 : 2
x= -7
1/7 c * (-7)= -7+c
-c= -7+c
-c-c= -7
-2c= -7
c= -7 : (-2)
c=3.5
Ответ: 3,5
3а-6а+2а-1=3а-6а=-3а+2а=-1а-1; вроде так
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А)4а во 2 (2а во 2 -3b в 3+1)
б)(х-6у)-(5-у)