486 : (5х + 2) = 18 5х + 2 = 486 : 18 5х + 2 = 27 5х = 27 - 2 5х = 25 Х = 25 : 5 Х = 5
Спасибо бальшое
486 : (5х + 2) = 18
5х + 2 = 486 : 18
5х + 2 = 27
5х = 27 - 2
5х = 25
Х = 25 : 5
Х = 5
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проверка:
486/(5*5+2)=18
486/(25+2)=18
486/27=18