Задание 31. Решите уравнение. A.

Решение:

1. \( x + 5 = 23 \)

• \( x = 23 - 5 \)
• \( x = 18 \)

2. \( x + 9 = 30 \)

• \( x = 30 - 9 \)
• \( x = 21 \)

3. \( 6 + x = 24 \)

• \( x = 24 - 6 \)
• \( x = 18 \)

4. \( 4 + x = 41 \)

• \( x = 41 - 4 \)
• \( x = 37 \)

5. \( x + 15 = 37 \)

• \( x = 37 - 15 \)
• \( x = 22 \)

6. \( x + 42 = 80 \)

• \( x = 80 - 42 \)
• \( x = 38 \)

7. \( 55 + x = 107 \)

• \( x = 107 - 55 \)
• \( x = 52 \)

8. \( 21 + x = 210 \)

• \( x = 210 - 21 \)
• \( x = 189 \)

9. \( 301 + x = 736 \)

• \( x = 736 - 301 \)
• \( x = 435 \)

10. \( x + 260 = 1000 \)

• \( x = 1000 - 260 \)
• \( x = 740 \)

11. \( x + 124 = 400 \)

• \( x = 400 - 124 \)
• \( x = 276 \)

12. \( 562 + x = 1865 \)

• \( x = 1865 - 562 \)
• \( x = 1303 \)

Ответ: 1. 18; 2. 21; 3. 18; 4. 37; 5. 22; 6. 38; 7. 52; 8. 189; 9. 435; 10. 740; 11. 276; 12. 1303.