For future reference, if you want to ask for help, then create a new topic rather than posting on someone else's.

Anyway, for these simultaneous equations you need to scale them up so that they have a common term, then combine them to give a simple linear equation.

2x-4y=16 --> (multiply by 3) 6x-12y=48

3x+6y=-12 --> (multiply by 2) 6x+12y=-24

Add these equations together: 6x-12y+6x+12y=48-24

12x=24

x=2

Knowing this, you can easily work out the other value.

2*2-4y=16

-4y=12

y=-3

Check: 3*2+6y=-12

6y=-18

y=-3

It works! So your final answer is **x=2, y=-3**