Final answer:
The axis of symmetry for a quadratic equation is most commonly found using the formula x = -b/(2a), which is derived from completing the square or the quadratic formula.
The Correct Option is; a) Completing the square
Step-by-step explanation:
The commonly used method to determine the axis of symmetry of a quadratic equation in the form ax²+bx+c = 0 is by using the formula for the axis of symmetry, which is derived from the process of completing the square or using the quadratic formula.
However, the direct formula to find the axis of symmetry is x = -b/(2a). This formula comes from recognizing that the vertex form of a quadratic equation can be written as a(x-h)²+k where (h, k) is the vertex, and the x-coordinate of the vertex, h, gives the line of symmetry.
While factoring can sometimes reveal the zeros or x-intercepts of the quadratic, it does not directly provide the axis of symmetry.
he method commonly used to determine the axis of symmetry of a quadratic equation is a) Completing the square. This method involves rewriting the quadratic equation in a perfect square form and finding the value of x that makes the equation equal to zero.
The x-coordinate of the vertex, which is the point where the axis of symmetry intersects the parabola, can then be determined.