Как решить уравнения (17x-8x+3)7=12 2472(15-x48)=206 (346-(x16-398))7=42

1. 17 х - 8 х + 3 = 12 7,

9 х + 3 = 84,

9 х = 84 - 3,

9 х = 81,

х = 81 : 9,

х = 9.

Проверяем:

(17 9 - 8 9 + 3) : 7 = 12,

(153 - 72 + 3) : 7 = 12,

84 : 7 = 12,

12 = 12.

2. 2472 : (15 - х : 48) = 206,

15 - х : 48 = 2472 : 206,

15 - х : 48 = 12,

х : 48 = 15 - 12,

х = 3 48,

х = 144.

Проверяем:

2472 : (15 - 144 : 48) = 206,

2472 : (15 - 3) = 206,

2472 : 12 = 206,

206 = 206.

3. 346 - (x : 16 - 398) = 42 7,

346 - х : 16 + 398 = 294,

744 - х : 16 = 294,

х : 16 = 744 - 294,

х : 16 = 450,

х = 450 16,

х = 7200.

Проверяем:

(346 - (7200 : 16 - 398)) : 7 = 42,

(346 - (450 - 398)) : 7 = 42,

(346 - 52) : 7 = 42,

294 : 7 = 42,

42 = 42.