Question

How do you solve the system using the elimination method for 2x - 4y =10 and -4x + 8y =-20?

Answer 1

Your system has `oo` solutions (it represents 2 coincident lines).

Explanation:

The second equation is equal to the first but multiplied by `-2`!
The two equations represent two coincident lines that will have an `oo` number of points in common and consequently the system will have `oo` solutions as well.

If you want you can multiply the first by `2` and add to the second;
`{color(red)(4x-8y=20`
`{-4x+8y=-20` add the two together you get:
`0=0` which is true.
This means that if you choose any set of coordinates that satisfy the first equation will satisfy the second as well:
For example:
`x=1 -> y=-2` for the first:
`x=1-> y=-2` for the second as well!

`x=2 -> y=-3/2` for the first;
`x=2 -> y=-3/2` for the second as well;
...etc.