Question

How do you solve `3x + y = 4` and `2x + y = 4`?

Answer 1

The solution for the system of equations is
`color(blue)(x=0,y=4`

Explanation:

`3x+color(blue)(y)=4`......equation `(1)`
`2x+color(blue)(y)=4`......equation `(2)`

Solving by elimination

Subtracting equation `1` from `2` would result in elimination of `color(blue)(y`

`3x+cancelcolor(blue)(y)=4`
`-2x-cancelcolor(blue)(y)=-4`

`color(blue)(x=0`

Substituting `x` in equation `1` to find `y`:

`3x+y=4`

`3 * 0 +y=4`
`0 +y=4`
`color(blue)(y=4`