Răspunsuri

2014-06-10T21:50:06+03:00
2014-06-10T22:00:39+03:00
Notam Ana cu a si Bianca cu b
a+b=24⇒a=24-b
a-3=b/5
inlocuim pe a cu 24-b
24-b-3=b/5
21-b=b/5
5(21-b)=b
105-5b=b
105=b+5b
105=6b
b=105/6
b=17.5
a=24-17.5
a=6.5
verificare:
6.5-3=17.5/5
3.5=3.5