Answer:
x+y=17
y can be 1,3,5,7 or 9
Let's start at 9
x+9=17
x=8
So the burner is 89
7, 5, 3 and 1 don't work
For example In order x+7=17, x should be 10, which is a contradiction; x is the one-digit number. If 7 doesn't work, lower numbers shouldn't work as well.
Explanation: