Ответ:

Пошаговое объяснение:

1)(x+9)/7=1+ (x+1)/3;

3*(x + 9) = 21*1 + 7*(x + 1)

3x + 27 = 21 + 7x + 7

3x + 27 = 28 + 7x

7x - 3x = 27 - 28

4x = -1

x = -1 : 4

x = -0,25

2)1- (5x-2)/6=(x-5)/9;

18*1 - 3*(5x - 2) = 2*(x - 5)

18 - 15x + 6 = 2x - 10

24 - 15x = 2x - 10

2x + 15x = 24 + 10

17x = 34

x = 34 : 17

x = 2

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

(3x + 4)/5 + (x - 7)/2 = (4x + 6)/5

2*(3x + 4) + 5*(x - 7) = 2*(4x + 6)

6x + 8 + 5x - 35 = 8x + 12

11x - 27 = 8x + 12

11x - 8x = 12 + 27

3x = 39

x = 39 : 3

x = 13

4)(7x-3)/2 - (9-4x)/3=(7-x)/2

3*(7x - 3) - 2*(9 - 4x) = 3*(7 - x)

21x - 9 - 18 + 8x = 21 - 3x

29x - 27 = 21 - 3x

29x + 3x = 21 + 27

32x = 48

x = 48 : 32

x = 1,5