Question

czas do środy daję 100 pkt ​

Answer 1

Verified answer

Odpowiedź:

1)

3(x + 7) = 5(2x - 11) + 4

3x+21 = 10x - 55 + 4

3x + 21 = 10x - 51

3x - 10x = - 51 + 21

- 7x = - 30

7x = 30

x= 30/7 = 4 2/7

2)

(x + 2)/3 - (3- x)/6 = - 1 | * 6

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

2x+ 4 - 3 + x = - 6

3x + 1 = - 6

3x = - 6 - 1 = - 7

x = - 7/3 = - 2 1/3

3)

1/3(1 - x) - 3/4(2 - 2x) = - 5/6 | * 12

4(1 - x) - 3 * 3(2 - 2x) = 2 * (- 5)

4 - 4x - 9(2 - 2x) = - 10

4 - 4x - 18 + 18x = - 10

14x - 14 = - 10

14x = - 10 + 14 = 4

x = 4/14 = 2/7

4)

(7x - 2)/3 - (3 - 2x)/4 = 1/6x - 2 | * 12

4(7x - 2) - 3(3 - 2x) = 2x - 2 * 12

28x - 8 - 9 + 6x = 2x - 24

34x - 17 = 2x - 24

34x - 2x =  - 24 + 17

32x = - 7

x = - 7/32

5)

(3x- 11)/4 - (2 + 5x)/2 = 2x - (3 - 2x)/6 - 13/4 | * 12

3(3x - 11) - 6(2 + 5x) = 12 * 2x - 2(3 - 2x) - 13 * 12

9x - 33 - 12 - 30x = 24x - 6 + 4x - 156

- 21x - 45 = 28x - 162

- 21x - 28x = - 162 + 45

- 49x = - 117

49x = 117

x = 117/49 = 2 19/49

6)

2x - 5(x - 1)/2 = 1 + x/3 | * 6

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

12x - 15(x-1) = 6 + 2x

12x - 15x + 15 = 6 + 2x

- 3x + 15 = 6 + 2x

- 3x - 2x = 6 - 15

- 5x = - 9

5x = 9

x = 9/5 = 1 4/5

7)

- 2(5x - 7) - 3x = 2(x - 8)

- 10x + 14 - 3x = 2x - 16

- 13x + 14 = 2x - 16

- 13x - 2x = - 16 - 14

- 15x = - 30

15x = 30

x = 30/15 = 2

8)

4x - 8 - (x + 3) + 2x = - (2x - 3)

4x - 8 - x - 3 + 2x = - 2x + 3

5x - 11 = - 2x + 3

5x+ 2x = 3 + 11

7x = 14

x = 14/7 = 2

9)

1 - (x - 2)/6 = - x + 3(x - 4)/4 | * 12

12 - 2(x - 2) = - 12x + 3 * 3(x - 4)

12 - 2x + 4 = - 12x + 9(x - 4)

- 2x + 16 = - 12x + 9x - 36

- 2x + 16 = - 3x - 36

- 2x + 3x = - 36 - 16

x = - 52

10)

(x + 1)/3 - 3x = - (2 - x) | * 3

x + 1 - 3x * 3 = - 3(2 - x)

x + 1 - 9x = - 6 + 3x

- 8x + 1 = - 6 + 3x

- 8x - 3x = - 6 - 1

- 11x = - 7

11x = 7

x = 7/11

11)

14 - (8 - 12x)/4 = 2(7 - x) + 6 | * 4

14 * 4 - 8 + 12x = 4 * 2(7 - x) + 6 * 4

56 - 8 + 12x = 8(7 - x) + 24

48 + 12x = 56 - 8x + 24

48 + 12x = 80 - 8x

12x + 8x = 80 - 48

20x = 32

x = 32/20 = 16/10 = 1 6/10 = 1 3/5

12)

(x² - x + 4)/3 + (2x - 7)/2 = x²/3 + 3x - 1 | * 6

2(x² - x + 4) + 3(2x - 7) = 2x² + 6 * 3x - 6

2x² - 2x + 8 + 3x - 21 = 2x² + 18x - 6

2x² + x - 13 = 2x² + 18x - 6

2x² - 2x² + x + 18x = - 6 + 13

19x = 7

x = 7/19

13)

(7 - 6x)/2 + 12 = (8x + 1)/3 - 10x | * 6

3(7 - 6x) + 12 * 6 = 2(8x + 1) - 10x * 6

21 - 18x + 72 = 16x + 2 - 60x

- 18x + 93 = - 44x + 2

- 18x + 44x = 2 - 93

26x = - 91

x = - 91/26 = - 3 13/26 = - 3 1/2

14)

x - 3(x - 1)/6 = 3x + 5 1/2  

x - (x - 1)/2 = 3x + 11/2 | * 2

2x - x + 1 = 3x * 2 + 11

x + 1 = 6x + 11

x - 6x = 11 - 1

- 5x = 10

5x = - 10

x = - 10/5 = - 2

15)

2x + 3(1 - 2x) = (8x + 10)/4 | * 4

8x + 3 * 4(1 - 2x) = 8x + 10

8x + 12(1 - 2x) = 8x + 10

8x + 12 - 24x = 8x + 10

- 16x + 12 = 8x + 10

- 16x - 8x = 10 - 12

- 24x = - 2

24x = 2

x = 2/24 = 1/12