Math Pattern Help
posted by Please Help .
Please help me to find out the missing y Numbers. I cannot figure out the pattern.
x Y
1 9
2 8
3 7
4
8
10
12 2
15
20

The x column increases by 1 and the Y column decreases by 1.
4  6
5  5
I'm sure you can take it from there. 
as the x increases by 1, the y appears to decrease by 1
y = x + 10
for x=4 , y = 4+10 = 6 , yup, that fits the pattern
for x =8, y = 8+10 = 2
etc.
(notice x=12, y=2 fits my pattern) 
Based on what you said this is what I came up with. Did I do the rest of the pattern correctly?
Thank you so much for your help.
X y
1 9
2 8
3 7
4 6
8 2
10 0
12 2
15 5
20 10 
12 7