Предмет: Математика, автор: vitalka78

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Автор ответа: dramionefeltsoncanon
1

Ответ:

На изи ваще

Пошаговое объяснение:

номер 1:

а) - 6

б) 7

в) - 6

г) 3

номер 2:

а) 3,2n + 18

б) n - k

в) - 2c - k

г) 3n

Автор ответа: Аноним
1

Ответ:

1.1)x=-6

2)x=7

3)x=-6

4)x=3

2.1)1.4

2)n-k

3)-2c-k

4)3n

Пошаговое объяснение:

1. 1) -2(15-x)=7x

-30+2x=7x

2x-7x=30

-5x=30

x=-6

2) 3x=-(x-28)

3x=-x+28

4x=28

x=7

3) 5x+12=-2(-4x-15)

5x+12=8x+30

5x-8x=30-12

-3x=18

x=-6

4) 8(4+x)=-5x+71

32+8x=-5x+71

8x+5x=71-32

13x=39

x=3

2.1) 3.2-1.2n-(-1.2n+1.8)=3.2-1.2n+1.2n-1.8=3.2-1.8=1.4

2) (2m+n)-(k+m)-m=2m+n-k-m-m=n-k

3) -2(c+a)-(k-2a)=-2c-2a-k+2a=-2c-k

4) 3m-5b-(-5b+3m-3n)=3m-5b+5b-3m+3n=3n

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