Your going to add the two equations to cancel out the x term. You get 6y=-36. Divide both sides by 6 and you get y=-6. Plug y in in your first equation and you'll get -4x-2(-6)=-12. Multiply the -2 by the -6 and you'll get -4x+12=-12. Subtract 12 from both sides and you get -4x=-24. Divide both sides by -4 and you get x=6. Your final answer is x=6, y=-6.