Question

Intr-o curte sunt porumbei si iepuri, in total 15 capete si 42 picioare. Cati porumbei si cati iepuri sunt? Va rog rezolvari complete

Answer 1

x=porumbei
y=iepuri
$\left \{ {{x+y=15} \atop {2x+4y=42}} \right.$⇔
$\left \{ {{2x+2y=30} \atop {2x+4y=42}} \right.$
Le scadem si vom obtine:-2y=-12
                                       -y=-6⇒y=6 iepuri
x+y=15
x+6=15⇒x=9 porumbei