how to find x in the following formula For a software project, I need to calculate some things. on of the formulas looks like:
26280 = 2 * SQRT((149,598,000,000 - x) / 1.4) + x / 10,217,588,910,387,300,000

My colegue says you can't solve the above equation (you won't be able to find x) I quite convinced you should be able to find x, the problem is, I don't know how :(
I came as far as rewriting the above into:
((26280 - x) / 20,435,177,820,774,600,000)^2 = (149,598,000,000 - x) / 1.4

but now I'm stuck.
Could anyone explain to me how to move on, in order to find x?

First, it's useful to write the expression in the standard quadratic form. For ease of reading/writing, I'm going to set $A = 20,435,177,820,744,600,00$ and $B = 149,598,000,000$.
$$
\begin{align*}
\left(\frac{26280 - x}{A}\right)^2 &= \frac{B - x}{1.4}\\
\frac{(26280 - x)^2}{A^2} &= \frac{B}{1.4} - \frac{x}{1.4}\\
\frac{26280^2 - 52560x - x^2}{A^2} &=  \frac{5}{7}B - \frac{5}{7}x\\
\frac{26280^2}{A^2} - \frac{52560x}{A^2} - \frac{x^2}{A^2} &= \frac{5}{7}B - \frac{5}{7}x\\
0 &= \frac{x^2}{A^2} + \left(\frac{52560}{A^2} - \frac{5}{7}\right)x + \frac{5}{7}B - \frac{26280^2}{A^2}.
\end{align*}
$$
You can finish this up with the quadratic formula.
EDIT: Alternatively, there is WolframAlpha.
