Question

Сложите уравнения в системе:

Answer 1

$1)+\left \{ {{7x+6y=6} \atop {2x+4y=-5}} \right.\\ --------\\9x+10y=1\\\\2)+\left \{ {{x-4y=-3} \atop {4x-2y=0}} \right.\\ --------\\5x-6y=-3\\\\3)+\left \{ {{2x+8y=-5} \atop {8x-8y=-1}} \right. \\--------\\10x=-6\\\\4)+\left \{ {{5x-7y=8} \atop {2x-6y=-6}} \right.\\ --------\\7x-13y=2$