Auto Goal Seek?

[PapaCheese]

I've got a fairly simple algebra equation that I've set up and solved in the attached spreadsheet by using goal seek. The red cells are the value of x (0.3) and the value of the whole equation (0).

Here's the equation:

0 = (0.7*300) + (0.3*x*2100) + (0.3*(1-x)*-1900)

Now, as I change the values of the non-red cells, I want Excel to always keep the result of the equation as 0 by adjusting the value of x without having to use goal seek every time I change a value, i.e. searching for the value of '0' in the results tab by using the 'x' cell as the variable cell. So kind of like an auto goal seek.

How would I do that?

[MrShorty]

The formula you have is, as you say, fairly simple. In my mind, the easiest way is to do the algebra outside of Excel to solve the given equation for x algebraically. Should be easy even if it is tedious. Once you have the expression for x, then program the cell containing x with that formula.