The ratio is 3:5 but you need to make more equivalent ratios
The simplest way to solve this is using the Law of Sines...
(sin68)/17=(sin53)/z
z=17sin53/sin68
z≈14.6 to nearest tenth of a unit
-4 & 8 -> this makes a total of 4
-2 & 6 -> this makes a total of 4
-1 & 5 -> this makes a total of 4
So now we have our three pairs with the same total.