Equation Generator

I want some code that will make equations based on variables and an end result that the user provides. It takes what information you give it and mixes it with signs and rearranges things until it makes an equation that works. A simple example would be to tell it that you have three variables (2, 6, and 9) and the end result would be 3. It would run until it came up with something like (2 * 9) / 6 = 3 or (2 * 6) - 9 = 3. It can only work with signs and the numbers you give it. It would be able to rearrange variables or even use multiples of the same variable if needed, but it could not introduce new variables. For instance, if it could not make an equation with 2, 6, and 9 then maybe it could if it used another 2 somewhere, but it could not just throw in a 5 to make something work. I would like it to have as wide a range as possible, meaning if it had to make a huge equation to make the numbers work or even use advanced math such as calculus it would be able. The more it can do the more likely it will be able to make equations no matter what you give it. And if all that is possible, I would like it to be taken a step further by making equations using multiple groups of variables and end results. Example: You give it variables (2, 6, 1, 4) with an end result of 1. And you give it (4, 10, 2, 7) with an end result of 0. It would run until it got one equation that fits both, such as (( A + B) / D) - C = X. (( 2 + 6) / 4) - 1 = 1 and (( 4 + 10) / 7) - 2 = 0.