Răspuns :
a+b=20
b=3a
inlocuim in problema initiala :
a +3a=20
4a=20
a=5
b=20-5
b=15
b=3a
inlocuim in problema initiala :
a +3a=20
4a=20
a=5
b=20-5
b=15
a=primul nr
b= al doilea nr
b=ax3
a+3a=20=>4a=20=>a=20:4=>a=5
b=20-5=15