1) 9x + 13 = 7x + 5

9x - 7x = 5 - 13

2x = -8

x = -8 / 2

x = -4.

2) 3(2x + 5) + 6 = 3

6x + 15 + 6 = 3

6x = 3 - 15 - 6

6x = -18

x = -18 / 6

x = -3.

3) 5x + 18 = 7x + 6(3x - 7)

5x + 18 = 7x + 18x - 42

5x - 7x - 18x = -42 - 18

-20x = -60

x= -60 / -20

x = 3.

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

3x - 21x + 28 = 10x - 35

3x - 21x - 10x = -35 - 28

-28x = -63

x = -63 / -28

x = 2,4.

5) 13 - 3(5x + 1) - 6(4x - 3) = 5x

13 - 15x - 3 - 24x + 18 = 5x

-15x - 24x - 5x = -18 + 3 - 13

-44x = -28

x= -28 / (-44)

x= 28/44 (дробь)

6) 4(x + 2) - 0,7 = 2(2x + 4) + 0,3

4x + 8 -0,7 = 4x + 8 + 0,3

4x - 4x = 8 + 0,3 - 8 + 0,7

0x = 1

Нет корней.