1) x + 25689 = 25689 + 37541
2) x + (6534 + 241) = (4173 + 6534) + 241
3) x ⋅ (25 ⋅ 37) = (42 ⋅ 25) ⋅ 37
⋅ - это умножить

1) х + 25689=25689+37541

х+ 25689=63230

х=63230-25689

х=37541

2)x + (6534 + 241) = (4173 + 6534) + 241

x + (6534 + 241) = 10707+241

x + (6534 + 241) = 10948

х+ 6775=10948

х=10948-677

х=10271

3)x ⋅ (25 ⋅ 37) = (42 ⋅ 25) ⋅ 37

x ⋅ (25 ⋅ 37) =1050⋅37

x ⋅ (25 ⋅ 37) =38850

х ⋅ 925 = 38850

х= 38850 : 925

х= 40, 8