Answer:
The correct answer is C) Completing the square.
Explanation:
In the first step of the derivation, the left-hand side of the equation is the standard form of a quadratic equation, with the variable x raised to the second power and the coefficient of x being 1. In the second step, the expression on the left-hand side is rewritten as the square of a binomial, with the constant term b/2a added to the binomial. This process of adding the constant term and then squaring the resulting binomial is called "completing the square." By completing the square, it is possible to rewrite the original quadratic equation in a form that can be easily solved using the quadratic formula.