Ответ:

Пошаговое объяснение:

7/24 = 2/(x-1)

7*(x - 1) = 24*2

7x - 7 = 48

7x = 48 + 7

7x = 55

x = 55:7

x = 7 6/7

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3/(2x-1) = 1/4

2x - 1 = 4*3

2x - 1 = 12

2x = 12 + 1

2x = 13

x = 13 : 2

x = 6,5

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9/2 = (x+3)/4

2*(x+3) = 9*4

2x + 6 = 36

2x = 36 - 6

2x = 30

x = 30:2

x = 15

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(5+x)/3 = 7/2

2*(5 + x) = 7*3

10 + 2x = 21

2x = 21 - 10

2x = 11

x = 11:2

x = 5,5