Question

How do you solve the system using the substitution method for x-2y=3 and x+y=1?

Answer 1

The solution for the system of equations is
`color(blue)( x=5/3, y=-2/3`

Explanation:

`x-2y = 3`
`x= color(blue)(3+2y`.......equation `(1)`

`x+y=1`......equation `(2)`

Substituting equation `(1)` in equation `(2)`
`x+y=1`
`color(blue)(3+2y)+y=1`
`3+3y=1`

`3y=2`
`color(blue)(y=-2/3`

Substituting the value of `y` in equation `(1)` to find `x`
`x= 3+2y`
`x= 3+2(-2/3)`

`x= 3-4/3`
`color(blue)(x= 5/3`