Verified answer

1)

[tex] \frac{x - 8}{x + 2} = \frac{7}{3} \\ 7(x + 2) = 3(x - 8) \\ 7x + 14 = 3x - 24 \\ 7x - 3x = - 24 - 14 \\ 4x = - 38 \\ x = - 38 \div 4 \\ x = - 9.5[/tex]

2)

[tex] \frac{x}{12} - \frac{x}{8} = \frac{7}{6} \: \: \: | \times 24 \\ 2x - 3x = 4 \times 7\\ - x = 28 \\ x = - 28[/tex]

3)

[tex] \frac{13x}{21} + \frac{9x}{14} = - 1 \: \: \: | \times 42\\ 2 \times 13x + 3 \times 9x = - 42 \\ 26x + 27x = - 42 \\ 53x = - 42 \\ x = - \frac{42}{53} [/tex]

4)

[tex] - \frac{3x}{10} - \frac{7}{15} = \frac{x}{6} \: \: \: | \times 30 \\ - 3x \times 3 - 7\times 2 = 5x \\ - 9x - 5x = 14 \\ - 14x = 14 \\ x = 14 \div ( - 14) \\ x = - 1[/tex]

Пошаговое объяснение:

(х - 8)/(х + 2) = 7/3

7(х + 2) = 3(х - 8)

7х + 14 = 3х - 24

7х - 3х = -24 - 14

4х = -38

х = -38 : (-4)

х = 9,5

х/12 - х/8 = 7/6 | * 24

2х - 3х = 28

-х = 28

х = -28

13х/21 + 9х/14 = -1 | * 42

26х + 27х = -42

53х = -42

х = -42 : 53

х = -42/53

- 3х/10 - 7/15 = х/6 | * 30

- 9х - 14 = 5х

-9х - 5х = 14

-14х = 14

х = 14 : (-14)

х = -1