Question

How do you solve x+5y=-7 and -x+2y=-8?

Answer 1

`y=-15/7`

`x=26/7`

Explanation:

`x+5y=-7" "(1)`
`-x+2y=-8" "(2)`

`"the sum of the two equation is"`

`cancel(x)-cancel(x)+5y+2y=-7-8`

`7y=-15`

`y=-15/7`

`"using (1) or (2)"`

`x+5(-15/7)=-7`

`x-75/7=-7`

`x=-7+75/7`

`x=(-49+75)/7`

`x=26/7`