 solve a system by elimination, we want to add down the columns of the equations in order to eliminate one of our variables. Now this particular example works out really nicely because I have 4y and negative 4y. If I add those together, since they're additive opposites, they'll just equal zero. So add down the rows. I have negative 3x plus negative, sorry, sorry, positive 3x minus 9x, that gives me negative 6x. 4y and negative 4y, they cancel each other out, so there's nothing there, plus zero y's, and that is equal to 12. So negative 6x is equal to 12, and therefore x, so we have x, x is equal to negative 2. Almost there, now we need a y value, so we can plug it in for the first or second equation to solve for y. So let's plug it into the first one, 3x plus 4y equals negative 1, and instead of our x, we're going to use the computed value that we just found, negative 2, and so that gives me negative 6 plus 4y is negative 1, add 6 to both sides, 4y is equal to 5, and so therefore y is 5 fourths, and so final answer, negative 2 and 5 fourths.