help solving an equation with vectors symbolically

Hello, 

I want to solve an equation with vectors symbolically.

The equation itself can be solved symbolically by Mathcad.

The symbolically result of the equation can not be shown, but it can be used if I assign the equation to a function. 

Now I want to use vectors with many data to get a solution for my unknown variable xB. I tried to use a Control variable i, but that did not work.

If the values are inserted into the equation directly, Mathcad finds two Solutions.

So my Question is if someone finds a way to get a solution for xB

and even if it is possible to solve an equation with vectors symbolically? 

The file is attached below.

Thank you for your help! 

Christina