Question

Rozwiąż układ równań

Answer 1

-2(5x-2y)+4(2x+y)=5
3(2x-y)-(y+7x)=6,5

-10x+4y+8x+4y=5
6x-3y-y-7x=6,5

-2x+8y=5
-x-4y=6,5/*(-2)

-2x+8y=5
2x+8y= -13
----------------
8y+8y=5-13
16y= -8/:16
y=-0,5

2x+8y= -13
2x+8*(-0,5)= -13
2x-4= -13
2x=-13+4
2x= -9/:2
x= -4,5

x= -4,5
y= -0,5

Answer 2

-10x+4y+8x+4y=5
6x-3y-y+7x=6.5


-2x+8y=5 /-8y
13x-4y=6.5

-2x=5-8y/2

x=5/2-8/2y
x=2.5-4y

13(2.5-4y)-4y=6.5

32.5-52y-4y=6.5
32.5-56y=6.5/-32.5

-56y=-26/56y
-y=0.464

y=-0.464
x=2.5-4(0.464)=2.5-1856=-1853.5