Verified answer

18х-5=553

18х=553+5

18х=558

х=558:18

х=31                      

18·31-5=553  (это проверка)

558-5=553

553=553

Verified answer

18х=553+5,18х=558, х=558:18,х=31, проверка: 18*31-5=553, 558-5=553,553=553.