Ответ:

1)11х-4х=9+19

7х=28

х=4

2)7х-10х-5=5х+15

-8х=20

х=-2.5

1)

11x - 9 = 4x + 19

11x - 4x = 19 + 9

7x = 28

x = 28 / 7

x = 4

2)

7x - 5 * (2x + 1) = 5x + 15

7x - 10x - 5 = 5x + 15

- 3x - 5x = 15 + 5

- 8x = 20

x = - 20 / 8

x = - 5 / 2