Ответ:

Пошаговое объяснение:

4(x + 2) = 9(x - 3)

4x + 8 = 9x - 27

9x - 4x = 8 + 27

5x = 35

x = 35:5

x = 7

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2(3x - 4) + 3 = 8x - 23

6x - 8 + 3 = 8x - 23

6x - 5 = 8x - 23

8x - 6x = 23 - 5

2x = 18

x = 18:2

x = 9

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1,2(2x - 3) = 0,5(4x + 3)

2,4x - 3,6 = 2x + 1,5

2,4x - 2x = 1,5+ 3,6

0,4x = 5,1

x = 5,1 : 0,4

x = 12,75

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2,1x - 3(2,5x + 3,6) = 10,4x - 7,64

2,1x - 7,5x - 10,8 = 10,4x - 7,64

-5,4x - 10,8 = 10,4x - 7,64

10,4x + 5,4x = -10,8 + 7,64

15,8x = -3,16

x = -3,16:15,8

x = -0,2

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