Quadratic Formula

From what i remember from my 9th grade summer, I believe you can derive the quadratic formula from ax^2+bx+c. However, i have forgotten that as of now... I am assuming the quadratic equation is :

x=-b+ or - (sqrt(b^2 - 4ac))/ 2a

I'm a bit rusty, it's summer afterall and i haven't used this since the beginning of calculus ><"

Edit:
Did you mean where did it come from as in country/civilization? because i can't help you there...
But if you want to derive the formula, use the completing the square method on the equation
ax^2+bx+c

Sorry if i can't be of any more use =O

I meant how you connect the ax^2+bx+c=0 to the Formula. :/