Ответ:

  1. \(x + 48 = 94\)
    \(x = 94 - 48 = 46\).
  2. \(234 + y = 452\)
    \(y = 452 - 234 = 218\).
  3. \(x - 174 = 206\)
    \(x = 206 + 174 = 380\).
  4. \(378 - b = 165\)
    \(b = 378 - 165 = 213\).

Ответ: 1) \(x=46\); 2) \(y=218\); 3) \(x=380\); 4) \(b=213\).