Hi, I'm not very good at Maths, so please be nice, I know the answer I'm trying to reach; Its the equation I'm trying to find:

Below is an image that is going to increase in size:

The image width is 500 and the height is 350. The position of X is

A(100 from the left)

B(46 from the top)

Now when the image size is increased from 500 to 600 wide, the height changes from 350 to 420.

X new Values are:

A(120 from the top)

B(55 from the left)

The question is... If X was anywhere on the page, what is the equation or maths to work out where it is when increasing the image width by N (this case 100).

Many Thanks.