Answer: 14.5 and 5.5
Explanation:
The issue is using whole numbers. 14+6=20, but 14-6=8. 15+5=20, but 15-5=10. If we use decimals, we can get in between the numbers a little to get 9. 14.5+5.5=20, but unlike 14+6, 14.5 gives 5 a tiny boost to push it to 14.5-5.5=9. Hope that helps!