Question

Please help!!!!! I will give a medal!!!!1



For the following system, if you isolated x in the first equation to use the Substitution Method, what expression would you substitute into the second equation?

-x - 2y = -4
3x + y = 12

-2y - 4

2y - 4

2y + 4

-2y + 4

Answer 1

x = -2y +4
just make x subject of formula in first equation :)

Answer 2

See, im new to this. How exactly would i do that.

Answer 3

Do i take away x and make it -2y + 4 +x

Answer 4

\[- x -2y = -4\]
\[-x = -4 + 2y\]
\[( \times -1) : -x \times -1 = -4 \times -1 + 2y \times -1\]
\[x = 4 -2y\]
which is same as : \[x = -2y +4\]

Answer 5

here is what i did to get x as Subject of formula if you dont understand some part just ask :)

Answer 6

I don't understand any of it.

Answer 7

ok you have equation number 1 : - x - 2y = -4
now you need an equation whereby you need to substitute the x value of the equation number 1 into equation number 2

Answer 8

positive x- value :
x = -2y +4

Answer 9

Oh okay, thank you!