Question

un elev are iepuri si porumbrei.Intrebat cati iepuri si cati porumbrei are,el a raspuns "in total sunt 15 si 34 picioare. Cati iepuri si porumbei are elevul?

Answer 1

x= iepuri
y =porumbei
x+y =15 capete   ;     x=15-y
4x+2y =34 picioare

4(15-y ) +2y =34
60-4y  +2y =34
2y =60-34
2y =26
y =13  porumbei
x =15-y
x =15-13 =2  iepuri