The function is odd just substitute f(x) for f(-x) and replace all the x's with -x's then go back to the original problem and substitute f(x) for -f(x) and multiply the original problem by -1 and since f(-x) and -f(x) are equal, it is odd. if the original problem, f(x) and f(-x) were equal it would be even and if none of the three are equal it would be neither. the answer to this question is odd because f(-x) and -f(x) are equal.
The purpose of the quadratic formula is to easily obtain the x-coordinate of the vertex's location. The goal is to solve the equation by isolating x on one side of the equation, just like you would any other equation.
In step 7, take the square root of both sides. Note that you must account for the negative side of the square root, so add the +/- to the right side (not necessary for the left side because you want the x to be positive when you are finished, and you still get the same answer even if you assume the left side is negative).
Next, subtract b/2a from both sides and simplify the denominator of the root to be 2a.
Finally combine the terms to have a single denominator.
