Помогите решить систему 8х+5у=5ху 4х+25у=7ху

Решите задачу:

$1)\; \left \{ {{8x+5y=5xy} \atop {4x+25y=7xy\, |\cdot(-2)}} \right. \; \left \{ {{8x+5y=5xy} \atop {-8x-50y=-14xy}} \right. \; \oplus \left \{ {{8x+5y=5xy} \atop {-45y=-9xy}} \right. \\\\2)\; \left \{ {{8x+5y=5xy\, |\cdot (-5)} \atop {4x+25y=7xy}} \right. \; \left \{ {{-40x-25y=-25xy} \atop {4x+25y=7xy}} \right. \; \oplus \; \left \{ {{-36x=-18xy} \atop {4x+25y=7xy}} \right.$

$3)\; \left \{ {{-36x=-18xy} \atop {-45y=-9xy}} \right. \; \left \{ {{y=\frac{-36x}{-18x}=2} \atop {x=\frac{-45y}{-9y}=5}} \right.$