Решите уравнения
-2x=6-7*(x+2)
3x-(5+x)=x-12
-2*(-4x+7)=-9+11

Відповідь:

1) -2x = 6-7*(x+2)

-2x = 6-7x-14

-2x = -8-7x

-2x+7x = -8

5x = -8

x = -1,6

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

3x-5-x = x-12

2x-5 = x-12

2x-x = -12+5

x = -7

3) -2*(-4x+7) = -9+11

8x-14 = 2

8x = 2+14

8x = 16

x = 2