## anonymous 5 years ago Derive the formula for the axis of symmetry to a quadratic equation.

1. anonymous

you just helped someone find the vertex of a parabola using the formula and now you want somemone to derive it for you?

2. anonymous

Anytime I write a question it usually "for fun".. :)

3. anonymous

U surely don't HAVE to.. :)

4. anonymous

okay thanks for the info

5. anonymous

Find the derivative and equate it to zero solve for x to get ur ans

6. anonymous

$y=ax^2+bx+c$ $y=a(x+\frac{b}{a})+c$ $y=a(x+\frac{b}{2a})^2+\color{red}{\text{who cares}}$ since first term is a perfect square it will be greater than or equal to zero if a is positive, less that or equal to zero if a is negative and it will be zero (so that is the max or min) if $x=-\frac{b}{2a}$

7. anonymous

derivative my foot

8. anonymous

If you don't care BOUNCE

9. anonymous

i don't care because if i need to find it i can alway replace x by $-\frac{b}{2a}$ i just don't care to try to keep track of what i added and subtracted. waste of time since i can find it easily

10. anonymous

I see.