Overloading allows us to provide different implementations of the same function depending on the number and type of arguments we pass. We can achieve the same thing using templates, where we can provide a common, generic implementation, regardless of argument type, specialising for more specific types where necessary. For instance, implementations that operate upon objects differ from those that operate upon pointers to objects; to cater for both we must overload the functions that provide those implementations.
Yes
It is x - y + 2 = 0
That is not a function, although it does involve the function of addition. A function is something that is done to numbers.
...a function call.
There is no such term as "building function" in C++.
Control is returning to the caller of the function.
yes,we can make function inline
They are at x = -3 and x = -2.
It is the first function that gets called when the program is executed.
There is no such thing. You probably meant the main function. The main function is the only function that is required as it serves as the entry point of the program.
Multi-function simply means more than one function. Every program must have at least one function, the main function (the entry point of the application), and although you can write an entire program using just this one function, breaking the program down into several smaller functions makes the code easier to read and maintain. A major advantage of multi-function programming is that functions can be called as often as required -- there is no need to write the same piece of code over and over again.
It is a quadratic function which represents a parabola.