Răspuns :
a+b+c=756
a-b=118 => a=b+118
a+2b+2c=1325
a+2b+2c=1325
a+b+c=756
___________(-)
b+c=569
a=756-569=187
b=187+118=305
c=569-b=569-305=264
a-b=118 => a=b+118
a+2b+2c=1325
a+2b+2c=1325
a+b+c=756
___________(-)
b+c=569
a=756-569=187
b=187+118=305
c=569-b=569-305=264
e cam inclcita rezolvare ce ti-o propun
a+b+c=756
a=b-118 din ambele =>
b-118+b+c=756
2b-118+c=756
2b+c=756+118
2b+c=874=>c=874-2b
daca dublez suma ultimilor doi termeni suma devine1325
a+2(b+c)=1325
a+2b+2c=874
stim de mai sus c=874-2b inlocuim si vom avea
a+2b+2(874-2b)=1325
a+2b+1748-4b=1325
a-2b+1748=1325
a-2b=1325-1748
a-2b=-423
stai din problema ca a=b-118 inlocium si vom avea
b-118-2b=-423
-b=-423+118
-b=-305->b=305
acum am aflat b=305 si stim ca a=b-118=> a=305-118=>a=187
a+b+c=756
a=187
b=305
187+305+c=756
492+c=756
c=756-492
c=264
verificam
daca dublez suma ultimilor doi termeni suma devine 1325 ??
b=305
c=264
suma lor:305+264=569
dublam suma 569x2=1138
adunam cu a=187
1138+187=1325
a+b+c=756
a=b-118 din ambele =>
b-118+b+c=756
2b-118+c=756
2b+c=756+118
2b+c=874=>c=874-2b
daca dublez suma ultimilor doi termeni suma devine1325
a+2(b+c)=1325
a+2b+2c=874
stim de mai sus c=874-2b inlocuim si vom avea
a+2b+2(874-2b)=1325
a+2b+1748-4b=1325
a-2b+1748=1325
a-2b=1325-1748
a-2b=-423
stai din problema ca a=b-118 inlocium si vom avea
b-118-2b=-423
-b=-423+118
-b=-305->b=305
acum am aflat b=305 si stim ca a=b-118=> a=305-118=>a=187
a+b+c=756
a=187
b=305
187+305+c=756
492+c=756
c=756-492
c=264
verificam
daca dublez suma ultimilor doi termeni suma devine 1325 ??
b=305
c=264
suma lor:305+264=569
dublam suma 569x2=1138
adunam cu a=187
1138+187=1325