Question

$left { { frac{x}{2}- { frac{y}{3} =1} atop { frac{x}{5}- frac{4}{4} =-1}} right.$

Answer 1

{3x-2y=6/*5⇒15x-10y=30
{4x-5y=-20/(-2)⇒-8x+10y=40
прибавим
7x=70
x=10
30-2y=6
2y=30-6
2y=24
y=12