Question

Решите задачу с помощью систем уравнений:()

Answer 1

$left { {{x+y=42} atop {x=frac{y}{2,5}} right. }} right. ; left { {{x+y=42} atop {x=frac{2y}{5}}} right. ; left { {{frac{2y}{5}+y=42} atop {x=frac{2y}{5}}} right. ; left { {{frac{7y}{5}=42} atop {x=frac{2y}{5}}} right. ; left { {{y=30} atop {x=12}} right.$