Răspuns :
notam cu a nr care se aduna, deci x+a=106, y+a=120 si z+a=144, dar x+a+y+a+z+a=106+120+144, sau 286+3a=370, sau 3a=84, deci a=28 rezulta x=106-28=78, y=120-28=92, z=144-28=116
a+b+c=286
a+n=106
b+n=120
c+n=144
a=106-n
b=120-n
c=144-n
106-n+120-n+144-n=286
370-3n=286
3n=84
n=28
si de aici inlocuiesti si tu n=28 in a,b,c,
a+n=106
b+n=120
c+n=144
a=106-n
b=120-n
c=144-n
106-n+120-n+144-n=286
370-3n=286
3n=84
n=28
si de aici inlocuiesti si tu n=28 in a,b,c,