x y
1 0 = -1
3 -2 = -5
5 -4 = -9
7 -6 = -13
As you can probably see, when you subtract a number from x to get y, it's different numbers each time. But when I decode it, I figure out that every time you subtract a number from x to get y, it's just 4 added to the subtracting number before that row.
I hope this helps, please Brainliest me, and have a great day! :D