Question

If `3x + 5y = 4` and `8y + 6x = 36`, what is the value of `-y`?

Answer 1

`-y=14`

Explanation:

`3x+5y=4`
`8y+6x=36`
`-y=?`
`3x+5y=4------------(1)`
`8y+6x=36------------(2)`
`(2)` can be simplified as
`3x+4y=18-----------(3)`
Subtracting (1) from (3)
`4y-5y=18-5`
`-y=14`