73-30+10-9-(89-20-50)

Решение:

\( 73 - 30 + 10 - 9 - (89 - 20 - 50) \)

1. \( 89 - 20 = 69 \)
2. \( 69 - 50 = 19 \)
3. \( 73 - 30 = 43 \)
4. \( 43 + 10 = 53 \)
5. \( 53 - 9 = 44 \)
6. \( 44 - 19 = 25 \)

Ответ: 25