Question

How do you solve the following system?: `x +3y =-2 , -7x +y = -9`

Answer 1

Here,`x+3y=-2`
`rArr x=-3y-2` ----eqn 1
Substitute this value of x in `-7x+y=-9`
We get `-7(-3y-2)+y=-9`
`rArr 21y+14+y=-9`
`rArr 22y=-9-14`
`rArr y=-23/22` ----eqn 2
Now, substitute this value in `x+3y=-2`
`rArr x+3xx-23/22=-2`
`rArr x-69/22=-2`
`rArr x=69/22-2`
`rArr x=25/22`

So, `(x,y)=(25/22, -23/22)`

Hope this helps :)