How to use a cell value as the "To value" value on Goal Seeking

Hello,

I have been looking for the solution for this problem for hours now, and I can't seem to find it, since the only results that show up when you include Excel goal seeking in your search are basci guides on how to use the Goal Seek feature.

A detailed description of my problem:
I am trying to implement a button in my worksheet, and the macro connected to it is supposed to Goal Seek with values informed by the user. I need the button implemented since most of the people who are going to use the worksheet are not much familiar with Excel.

So, the question is, how do I use a cell value for the "To value" field of the Goal Seek feature?

The picture below illustrates my problem - I want to reach a minimun of Y on Z by variating X.
goal_seek.png


Thanks in advance