Question

3x-7y=28? x+y=6?

Answer 1

`y=-1`
`x=7`

Explanation:

`3x-7y=28`
`x+y=6`

Solve by elimination:
`3x-7y=28`
`-3(x+y=6)`

Which is:
`cancel(3x)-7y=28`
`cancel(-3x)-3y=-18`
`-10y=10`
`y=-1`

Solve for `x` by substituting `y`:
`x-1=6`
`x=7`