Question

Решите систему уравнений:

2x+y=1
5x+2y=0

Answer 1

$left { {{2x+y=15} atop {x+2y=0}} right. \\ left { {{2(-2y)+y=15} atop {x=-2y}} right.\\ left { {{-4y+y=15} atop {x=-2y}} right.\\ left { {{-3y=15|:(-3)} atop {x=-2y}} right.\\ left { {{y=-5} atop {x=-2*(-5)}} right. \\ left { {{y=-5} atop {x=10}} right. \\(10;-5)$