Multiplying the first equation by -1 and adding it to the second, we get that
8x =40 or -8x=-40. Dividing both sides by 8, we get x=5 and plugging it into the first equation, we get -15+2y=23, and adding 15 to both sides we get 2y=38. Dividing both sides by 2, we get 38/2=19