Question

ПОМОГИТЕ!!!!!!!!!!!!!!!!!!!!!!!1
1.решите систему уравнений;
4у+20=2(3х-4у)-4
16-(5х+2у=3х-2у

2.решие систему уравнений
2(2х-у)+3(2х-у)=32
5(2х-у)-2(2х+у)=4

Answer 1

№1
$left { {{4y+20=2(3x-4y)-4} atop {16-(5x+2y)=3x-2y}} right. left { {{4y+20=6x-8y-4} atop {16-5x-2y=3x-2y}} right. left { {{12y-6x=-24|:6} atop {-8x=-16|:(-8)}} right. left { {{2y-x=-4} atop {x=2}} right. 2y-2=-4 2y=-2 y=-1 2*(-1)-x=-4 -2-x=-4 -x=-2 x=2$
Ответ:(2;-1)

№2
$left { {{2(2x-y)+3(2x-y)=32} atop {5(2x-y)-2(2x+y)=4}} right. left { {{4x-2y+6x-3y=32} atop {10x-5y-4x-2y=4}} right. left { {{10x-5y=32|:5} atop {6x-7y=4}} right. left { {{2x-y=6.4} atop {6x-7y=4}} right. -y=6.4-2x y=2x-6.4 6x-7(2x-6.4)=4 6x-14x+44.8=4 -8x=-40.8 x=5.1 2*5.1-y=6.4 10.2-y=6.4 -y=-3.8 y=3.8$
Ответ:(5.1;3.8)