Răspuns :
a+b+c=39
b=c+1
a=b+7⇒a=c+8
c+8+c+1+c=39
3c=39-9
3c=30
c=30:3
c=10
b=10+1=11
a=11+7=18
V: 18+11+10=39
b=c+1
a=b+7⇒a=c+8
c+8+c+1+c=39
3c=39-9
3c=30
c=30:3
c=10
b=10+1=11
a=11+7=18
V: 18+11+10=39
a+b+c=39
b-1=c b=c+1
a-7=b
a+a-7+a-7-1=39
3a=39+15
3a=54
a=18
b=11
c=10
Vf. 18+11+10=39
b-1=c b=c+1
a-7=b
a+a-7+a-7-1=39
3a=39+15
3a=54
a=18
b=11
c=10
Vf. 18+11+10=39