This allows you to pass a complex (or simple) string and it will solve it for you.
ComplexEquations solver = new ComplexEquations();
string value = solver.Calculate("-222.120389 (-4 / -2) - 22.1230 + (10.98372 - -5) - 500 ^ 2");
Console.WriteLine(value);
I plan on adding more features in the future. This includes solving for a letter, linear equations, etc.