№ 3. Решите уравнения: 1) 28,9-x = 5,347; 2) (x-23,427) - 7,94 = 6,873; 3) (81-x) + 27,8 = 39,156.

Решение:

1. 28,9 - x = 5,347
   x = 28,9 - 5,347
   x = 23,553
2. (x - 23,427) - 7,94 = 6,873
   x - 23,427 = 6,873 + 7,94
   x - 23,427 = 14,813
   x = 14,813 + 23,427
   x = 38,24
3. (81 - x) + 27,8 = 39,156
   81 - x = 39,156 - 27,8
   81 - x = 11,356
   x = 81 - 11,356
   x = 69,644

Ответ:

• 1) x = 23,553
• 2) x = 38,24
• 3) x = 69,644