Question

How do solve the following linear system?: `-2x -8y = 4 , 3x-y=3`?

Answer 1

`x=10/13, y = -9/13`

Explanation:

To solve by elimination you will need to make coefficients of x or y "match" so that when you add or subtract the equations one of the variables will be eliminated.

If we multiply the second equation by 8 we get:
`-2x - 8y = 4`
`24x - 8y = 24`

Now if we subtract the two new equations, we will eliminate y and will be able to solve an equation in x.

`26x = 20`
`x=10/13`

Substitute this back into one of the original equations to find y.

`3*10/13 - y =3`
`30/13 - y = 3`
`-y=9/13`
`y=-9/13`