Răspuns :
a+b+c=138
a=b-13 =>b=a+13
a=2c =>c=a/2
a+a+13+a/2=138
2a+2a+26+a+276
5a=276-26
5a=250
a=50
b=63
c=25
a=b-13 =>b=a+13
a=2c =>c=a/2
a+a+13+a/2=138
2a+2a+26+a+276
5a=276-26
5a=250
a=50
b=63
c=25
cred ca este o greseala in enunt dar incerc o rezolvare
notam nr cu a,b si c si avem a+b+c=138
a=b-13 b=a+13
a=2c c=a/2 si inlocuim in ecuatie
a+a+13+a/2=138 2a+13+a/2=138 4a+26+a=276 5a=276-26 5a=250 a=50
b=a+13=25+13=38
c=2c=2*25=50
notam nr cu a,b si c si avem a+b+c=138
a=b-13 b=a+13
a=2c c=a/2 si inlocuim in ecuatie
a+a+13+a/2=138 2a+13+a/2=138 4a+26+a=276 5a=276-26 5a=250 a=50
b=a+13=25+13=38
c=2c=2*25=50