Как необходимо решать? х 9(8+х) =10+9; 3х 8(9+х) =х+6;

1) х - 9 (- 8 + х) = - 10 + 9;

x + 9 * 8 - 9 * x = - 1.

x + 72 - 9x = - 1.

- 8x = - 1 - 72.

- 8x = - 73.

x = 73/8 = 9 1/8.

Ответ: х = 9 1/8,

2) 3х - 8 (9 + х) = - х + 6;

3x - 8 * 9 - 8 * x + x = 6.

4x - 72 - 8x = 6.

- 4x = 6 + 72.

- 4x = 78.

x = - 78 : 4 = 19,5,

Ответ: х = 19,5,

3) 7х - 3 (1 + 5х) =2х + 8;

7x - 3 * 1 - 3 * 5x - 2x = 8.

5x - 3 - 15x = 8.

- 10x = 8 + 3.

- 10x = 11.

x = - 11/10 = - 1.1.

Ответ: х = - 1,1,

4) 2 + 3 (1 + 10х) = 4х - 9,

2 + 3 * 1 + 3 * 10х - 4х = - 9,

5 + 30x - 4x = - 9.

26x = - 9 - 5.

26x = - 14.

x = - 14/26 = - 7/13.

Ответ: х = - 7/13.