How to run a function that is run by a function?

Hi all

I have a function A that has a system of equations. A function B that calls that function A and solves the system of equations via fsolve. Now I have a third m. File from which I want to call the function B to solve the equation for several inputs. This third file creates a parameter d that should be placed in the formulas of the function A, so i made function A double input x, d. And then should be solved via function B which is fsolve. How should I do it? Since when I call function B name in the third file, it says undefined variable x, which should the input in function A and output of function B

[Walter Roberson]

I am confused but I suspect you need

http://www.mathworks.com/help/matlab/math/parameterizing-functions.html