Răspuns :
x+y=600......................
x+57=y+35......................
(x+57)+(y+35)=x+y+57+35=600+92=692 ........................
x+57=y+35=692/2=346..............
x=346-57=289.................
y=346-35=311...................
verificare: 289+311=600.
a+b=600
600+(57+35)
=600+92
=692
692:2=346
x=346-57=289
y=346-35=311
v:289+311=600
600+(57+35)
=600+92
=692
692:2=346
x=346-57=289
y=346-35=311
v:289+311=600