Answer the following questions related to the zeros of a quadratic polynomial.
(i) Define the zero (or root) of a polynomial.
(ii) Explain geometrically what the zeros of a quadratic polynomial represent on the Cartesian plane.
(iii) A quadratic polynomial satisfies b2−4ac=0. Describe how its graph meets the x–axis and state the number of zeros it possesses, giving reasons for your answer.