Question

How do you find the solution of the system of equations `-3x + y = -4` and `3x + y = -4`?

Answer 1

We can add the two equations to eliminate `3` `x`

Adding the 2 equations will give us:

`(y - 3x) +(y + 3x) = -4 + -4`

`y - cancel(3x) + y+ cancel(3x) = -8`

`2y= -8`
`color(blue)(y = -4)`

Substituting this value of `y` in the second equation we get `x` :

we are given:
`3x + y = -4`

`3x = -4 -y`
`3x = -4 +4`
`3x = 0`

`color(blue)(x =0)`

The solution to these system of equations is:

`color(blue)(x = 0 , y = -4`