solve the second equation for x to get x=-9-y, the plug it in into the first equation, so you get 2(-9-y) -3y = 12, distribute the 2, so you get -18-2y-3y=12, add like terms so you get -18-5y = 12, then move the constants to the right so you get -5y = 30 and solve to get y=-6, and then plug it into x=-9-y to get x=-3