Help with x position function please

[Duffel]

Help. I need a function to describe the position of an object relative to it's size and another object.

The problem:
There are two objects. (say, circles of equal size)
At size 100% they have the same x position. (for simplicity say, x = 0)
As the objects increase in size (at an equal rate) the x position of Object 2 changes.
At size 200% the x position of Object 2 would be +20 (the x position of Object 1 + 20)
At size 50% the x position of Object 2 would be -5.

I need a function that would describe the position of Object 2 as the objects increase or decrease in size (from 10% to 500%).

Can someone help or point me in the right direction for a solution?

[OpethRockr55]

Are you looking for something that is a relationship? Like for every 10% off you are from 100% you modify by that amount? (Example: %10, or 90% off would equal a - 9 change in the x position)

[Duffel]

That's a nice direct way to think of it. The relationship may not be that constant (my example was misleading) but I'll try it and see how it works visually. Thanks for your help OpethRockr55.

[vlad2005]

if u want an linear relationship, this can be easely done. But if u want another variations modell, than can be more complicated. Be more exactly.
Problem is ti establish an mathematical equation for that. This can be done if u know what u want (what kind of variation).

[Nialsh]

submit some example pictures