Question

How do solve the following linear system?: `x + 3y = 9 , y= -2x + 1`?

Answer 1

`x=-6/5,y=17/5`

Explanation:

Plugging
`y=-2x+1` in the first equation we get
`x+3(-2x+1)=9`
so
`x-6x+3=9`
`-5x+3=9`
`-5x=6`
`x=-6/5`
so
`y=12/5+5/5=17/5`