Question

Question #b8d66

Answer 1

`y=4`

`x=2`

Explanation:

If `4x-2y=0` and `4x+y=12`, then:

`4x-4x+y-(-2y)=12-0`

`=> 0x+y+2y=12`

`=> 3y=12`

`=> y=4`

Since

`4x+y=12`

we get that

`4x+4=12`

`=> 4x=12-4`

`=> 4x=8`

`=> x=2`

So `y=4` and `x=2`.

Answer 2

`x=2 and y=4`

Explanation:

Notice that the `x` terms are exact;y the same in both equations.

If you subtract the equations, the `x` terms will be eliminated and you will be able to solve for `y`

`" "4x +y =12" "rarr A`
`" "4x -2y =0" "rarr B`

`A-B:" " 0x+3y =12" "rarrC`

`color(white)(wwwwwwwwwww)y = 4`

Once you know the value for `y` you can use it to find `x`

Substitute `4 " for " y " in " A`

`" "4x +y =12" "rarr A`
`" "4x +(4) =12`

`" "4x = 8`
`" "x =2`

Check in `B`

`" "4x -2y =0" "rarr B`
`" "4(2) -2(4) =0`
`" "8-8=0`