looks blue and gold to me <| sep |> Nothing wrong with doing it over 12 instead of 24 . It just involves a few extra steps , because you had to simplify first , and then put the fractions over a common denominator . I went for the common denominator right away , but then eventually simplified to a fraction with a denominator of 12 , so . Anyway , you got the right equations this time 18 x 13 y 30 20 x 2 y 24 And then you multiplied the first equation by 2 , and the second by 13 , and then added them . That ' s all good . However , when you get here 224 x 252 You conclude that x 98 . But note that both sides of the equation are negated . If you divide 252 by 224 , you get 98 , not 98 . The final answer is actually x 98 , y 34 . Once you get the right x , check your working when finding y as well .