x^2 in the function that you typed is x * x ( x multiplied by x). It represents a second degree because there are only 2 "x"s multiplied together. If there were 3 "x"s multiplied together, we would have x^3. Since the highest exponent in this function is 2 (in x^2), we call this function a 2nd degree polynomial.
Addition, I would use the principles of addition.
