Respuesta :

Answer:

[tex](x=3,y=-9)[/tex]

Step-by-step explanation:

The given systems is;

[tex]1.2x + 2.4y = - 18 \\ - 0.8x + 0.4y = 6[/tex]

Divide the top equation by 1.2 and the bottom equation by by 0.8 to get:

[tex]x + 2y = - 15 \\ - x + 0.5y = 7.5[/tex]

Now add both new equations:

[tex]2y + 0.5y = 15 + - 7.5[/tex]

[tex]2.5y = 7.5[/tex]

[tex]x = \frac{7.5}{2.5} = 3[/tex]

Let us substitute x=3 into x+2y=-15 and solve for y.

3+2y=-15

2y=-15-3

2y=-18

y=-9

The solution is (x=3,y=-9)