Răspuns :
279x3-a=379
837-a=379
a=837-379
a=458
...............................
29x56+a=6000
1624+a=6000
a=6000-1624
a=4376
.........................................
a+70x52=6142
a+3640=6124
a=6124-3640
a=2484
..............................
a-153x25=4
a-3825=4
a=4+3825
a=3829
837-a=379
a=837-379
a=458
...............................
29x56+a=6000
1624+a=6000
a=6000-1624
a=4376
.........................................
a+70x52=6142
a+3640=6124
a=6124-3640
a=2484
..............................
a-153x25=4
a-3825=4
a=4+3825
a=3829
a).
279x3-a=379
837-a=379
a=837-379
a=458
b).
29x56+a=6000
1624+a=6000
a=6000-1624
a=4376
c).
a+70x52=6142
a+3640=6142
a=6124-3640
a=2484
d).
a-153x25=4
a-3824=4
a=3824+4
a=3828.
(^-^)
279x3-a=379
837-a=379
a=837-379
a=458
b).
29x56+a=6000
1624+a=6000
a=6000-1624
a=4376
c).
a+70x52=6142
a+3640=6142
a=6124-3640
a=2484
d).
a-153x25=4
a-3824=4
a=3824+4
a=3828.
(^-^)