Ответ:

Пошаговое объяснение:

ВАРИАНТ 1

1.

7-2x=9-3x

3x - 2x = 9 - 7

x = 2

2.

11x=6+5(2x - 1)

11x = 6 + 10x - 5

11x = 1 + 10x

11x - 10x = 1

x = 1

3.

6(2x-3)-3x = 2x - 4

12x - 18 - 3x = 2x - 4

9x - 18 = 2x - 4

9x - 2x = 18 - 4

7x = 14

x = 14:7

x = 2

4.

4(3x+5)-5(4x-3) = 3

12x + 20 - 20x + 15 = 3

-8x + 35 = 3

8x = 35 - 3

8x = 32

x = 32:8

x = 4

5.

5x-3(4x-1) = 7 - 2(7x+2)

5x - 12x + 3 = 7 - 14x - 4

-7x + 3 = 3 - 14x

14x - 7x = 3 - 3

7x = 0

x = 0

6.

-5,6(x-3)+2.1x=-3,5x+10

-5,6x + 16,8 + 2,1x = -3,5x + 10

-3,5x + 16,8 = -3,5x + 10

3,5x - 3,5x = 10 - 16,8

0 = -6,8

x  ≠ -6,8 (уравнение не имеет корней)

ВАРИАНТ 2

1.

7x+10=5x+2

7x - 5x = 2 - 10

2x = -8

x = -8:2

x = -4

2.

4(3x-2) + 5 =9

12x - 8 + 5 = 9

12x - 3 = 9

12x = 9+3

12x = 12

x = 12:12

x = 1

3.

2x-5=7(3x+4) +5

2x - 5 = 21x + 28 + 5

2x - 5 = 21x + 33

21x - 2x = -33 - 5

19x = -38

x = -38:19

x = -2

4.

28-4(3x + 2) = 5(2x-7)

28 - 12x - 8 = 10x - 35

20 - 12x = 10x - 35

10x+12x = 20 + 35

22x = 55

x = 55:22

x = 2,5

5.

3x-4(5x + 2) - 6(3x-4)= 1

3x - 20x - 8 - 18x + 24 = 1

-35x + 16 = 1

35x = 16 - 1

35x = 15

x = 15:35

x = 3/7

6.

7(x-4)+ 3 = 3(2x − 7) + x-8

7x - 28 + 3 = 6x - 21 + x - 8

7x - 25 = 7x - 29

7x - 7x = -29+25

0 = -4

0 ≠ -4 (уравнение не имеет корней)

ВАРИАНТ З

1.

5-6x=-10x-3

10x - 6x = -3 - 5

4x = -8

x = -8:4

x = -2

2.

6(2x+5)-8x=2

12x + 30 - 8x = 2

4x + 30 = 2

4x = 2 - 30

4x = -28

x = -28 : 4

x = -7

3.

3 + 4(5x-3) = 4x+7

3 + 20x - 12 = 4x + 7

20x - 9 = 4x + 7

20x - 4x = 7+9

16x = 16

x = 16:16

x = 1

4.

3(5x-7)-7(4x+5) = x

15x - 21 - 28x - 35 = x

-13x - 56 = x

13x+x = -56

14x = -56

x = -56:14

x = -4

5.

2(6x-5)-7(3x - 5) = 4x-1

12x - 10 - 21x + 35 = 4x - 1

-9x + 25 = 4x - 1

4x + 9x = 25 + 1

13x = 26

x = 26:13

x = 2

6.

−12x+4(x − 3) = − 8x − 12.

-12x + 4x - 12 = -8x - 12

-8x - 12 = -8x - 12

8x - 8x = 12 - 12

0 = 0

x  є (-∞ ; ∞) (уравнение имеет множество решений)