Respuesta :
The given system of equation:
[tex]6x+2y=-6 \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\times 2 \\ 3x-4y=-18 \\ \\ 12x+4y=-12 \\ \underline{3x-4y=-18 \ \ } \\ 15x=-30 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 15 \\ x=-2 \\ \\ 3x-4y=-18 \\ 3 \times (-2)-4y=-18 \\ -6-4y=-18 \ \ \ \ \ \ \ \ \ \ \ \ |+6 \\ -4y=-12 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div (-4) \\ y=3 \\ \\ (x,y)=(-2,3)[/tex]
Answer options:
1.
[tex]12x+4y=-12 \\ 15x=-30 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 15 \\ \\ 12x+4y=-12 \\ x=-2 \\ \\ 12 \times (-2)+4y=-12 \\ -24+4y=-12 \ \ \ \ \ \ \ \ \ \ |+24 \\ 4y=12 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 4 \\ y=3 \\ \\ (x,y)=(-2,3) \\ \hbox{the same solution}[/tex]
2.
[tex]8x+4y=-4 \\ 14x=-10 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 14 \\ \\ 8x+4y=-4 \\ x=-\frac{10}{14}=-\frac{5}{7} \\ \\ x=-\frac{5}{7} \not= -2 \\ \hbox{not the same solution}[/tex]
3.
[tex]6x-8y=-36 \\ -6y=-42 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div (-6) \\ \\ 6x-8y=-36 \\ y=7 \\ \\ y=7 \not= 3 \\ \hbox{not the same solution}[/tex]
4.
[tex]6x-y=-15 \\ 3y=9 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 3 \\ \\ 6x-y=-15 \\ y=3 \\ \\ 6x-3=-15 \ \ \ \ \ \ \ \ \ |+3 \\ 6x=-12 \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 6 \\ x=-2 \\ \\ (x,y)=(-2,3) \\ \hbox{the same solution}[/tex]
The equivalent systems of equations are 1 and 4:
12x+4y=-12
15x=-30
and
6x-y=-15
3y=9
[tex]6x+2y=-6 \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\times 2 \\ 3x-4y=-18 \\ \\ 12x+4y=-12 \\ \underline{3x-4y=-18 \ \ } \\ 15x=-30 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 15 \\ x=-2 \\ \\ 3x-4y=-18 \\ 3 \times (-2)-4y=-18 \\ -6-4y=-18 \ \ \ \ \ \ \ \ \ \ \ \ |+6 \\ -4y=-12 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div (-4) \\ y=3 \\ \\ (x,y)=(-2,3)[/tex]
Answer options:
1.
[tex]12x+4y=-12 \\ 15x=-30 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 15 \\ \\ 12x+4y=-12 \\ x=-2 \\ \\ 12 \times (-2)+4y=-12 \\ -24+4y=-12 \ \ \ \ \ \ \ \ \ \ |+24 \\ 4y=12 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 4 \\ y=3 \\ \\ (x,y)=(-2,3) \\ \hbox{the same solution}[/tex]
2.
[tex]8x+4y=-4 \\ 14x=-10 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 14 \\ \\ 8x+4y=-4 \\ x=-\frac{10}{14}=-\frac{5}{7} \\ \\ x=-\frac{5}{7} \not= -2 \\ \hbox{not the same solution}[/tex]
3.
[tex]6x-8y=-36 \\ -6y=-42 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div (-6) \\ \\ 6x-8y=-36 \\ y=7 \\ \\ y=7 \not= 3 \\ \hbox{not the same solution}[/tex]
4.
[tex]6x-y=-15 \\ 3y=9 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 3 \\ \\ 6x-y=-15 \\ y=3 \\ \\ 6x-3=-15 \ \ \ \ \ \ \ \ \ |+3 \\ 6x=-12 \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\div 6 \\ x=-2 \\ \\ (x,y)=(-2,3) \\ \hbox{the same solution}[/tex]
The equivalent systems of equations are 1 and 4:
12x+4y=-12
15x=-30
and
6x-y=-15
3y=9
Answer:12x+4y=-12
15x=-30
Step-by-step explanation:
just took the test and had to use the answer below to get it right but they got to answers :// thats dumb but theres the answer start forward
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