Răspuns :
3*574=2a
1722=2a
a=1722:2
a=861
[(5a+19)x7-2]:9=34
(5a+19)x7-2=34x9
(5a+19)x7-2=306
(5a+19)x7=306+2
(5a+19)x7=308
5a+19=308:7
5a+19=44
5a=44-19
5a=25
a=25:5
a=5
1722=2a
a=1722:2
a=861
[(5a+19)x7-2]:9=34
(5a+19)x7-2=34x9
(5a+19)x7-2=306
(5a+19)x7=306+2
(5a+19)x7=308
5a+19=308:7
5a+19=44
5a=44-19
5a=25
a=25:5
a=5