Verified answer

Ответ:

[tex]7300 + (3000 - x) = 9500 \\ 3000 - x = 9500 - 7300 \\ 3000 - x = 2200 \\ - x = 2200 - 3000 \\ - x = - 800 \\ x = 800[/tex]

проверка:

[tex]7300 + (3000 - 800) = 9500 \\ 7300 + 2200 = 9500 \\ 9500 = 9500[/tex]