a=varsta Daniela
b-varsta tata
c-varsta bunica
a+b+c=90
b+2=8(a+2) =>b+2=8a+16 =>b=8a+14 (1)
c+2=2b (2)
Inlocuim (1) in (2)
c+2=2(8a+14)
c+2=16a+28 => c=16a+26 (3)
Inlocuim (1) si (3) in prma relatie
a+b+c=90
a+8a+14+16a+26=90
25a=90-40
25a=50
a=2 varsta Daniela
b=8a+14=8*2+14=30 varsta tata
c=16a+26=16*2=26=32+26=58 varsta bunica