347 + (650 : y - 28) = 449

347 + (650:у -28) =449 650:у -28 = 449-347 650:у - 28 = 102 650:у = 102+28 650:у= 130 у= 650:130 у= 5 проверим: 347 + (650:5 -28) =449 347+ (130-28)=449 347 +102=449 449=449