Question

решите систему уровнений
4х= -6у
7у-2х=20

Answer 1

$left { {{4x=-6y} atop {7y-2x=20}} right. \ \ left { {{4x=-6y} atop {14y-4x=40}} right. \ \ 14y-(-6y)=40 \ 14y+6y=40 \ 20y=40 \ y=2 \ \ 4x=-6*2 \ 4x=-12 \ x=-3 \ \ left { {{x=-3} atop {y=2}} right.$

Answer 2

4x=-6y⇒2x=-3y
7y-2x=20⇒7y+3y=20⇒10y=20⇒y=2
x=-1,5y=-1,5*2=-3
(-3;2)