Question

x/y=2/7 si x+y=90 aflati x si y

Answer 1

$\frac{x}{y} = \frac{2}{7}$ 
$\frac{x+y}{2+7} = \frac{90}{9} =10 \to x=10*2 \text{ } si \text{ } 10*7 \\ \boxed{x=20} \\ \boxed{y=70}$

Verificare: x+y=90 echivalent cu 20+70=90 (Adevarat)