ПЛИИИИИЗЗ!!ПРОШУУ Фото в приложении)Выполнить методом сложения

Решите задачу:

$\left \{ {{x+4y=39} \atop {2x-y=15}} \right. \left \{ {{x=39-4y} \atop {78-8y-y=15}} \right. \left \{ {x=39-4y} \atop {-9y=-63}} \right. \left \{ {{x=39-28} \atop {y=7}} \right. \left \{ {{x=11} \atop {y=7}} \right.$ $\left \{ {{5x+y=20} \atop {2x-y=1}} \right \left \{ {{y=20-5x} \atop {2x-20+5x=1}} \right. \left \{ {{y=20-5x} \atop {7x=21}} \right. \left \{ {{y=20-15} \atop {x=3}} \right. \left \{ {{y=5} \atop {x=3}} \right.$

$\left \{ {{2x+3y=2} \atop {-2x+5y=-18\right. \left \{ {{2x=2-3y} \atop {-2+3y+5y=-18}} \right. \left \{ {{2x=2-3y} \atop {8y=-16}} \right. \left \{ {{x= \frac{2+6}{2}} \atop {y=-2}} \right. \left \{ {{x=4} \atop {y=-2}} \right.$

$\left \{ {{2x-3y=9} \atop {4x+3y=27}} \right. \left \{ {{2x-3y=9} \atop {3y=27-4x}} \right. \left \{ {{2x-27+4x=9} \atop {3y=27-4x}} \right. \left \{ {{6x=36} \atop {3y=27-4x}} \right. \left \{ {{x=6} \atop {y= \frac{27-24}{3} }} \right. \left \{ {{x=6} \atop {y=1}} \right.$

$\left \{ {{x+4y=39} \atop {2x-y=15}} \right. \left \{ {{x=39-4y} \atop {78-8y-y=15}} \right. \left \{ {{x=39-4y} \atop {-9y=-63}} \right. \left \{ {{x=39-28} \atop {y=7}} \right. \left \{ {{x=11} \atop {y=7}} \right.$