Explain how to solve a quadratic equation using the quadratic formula method?

Quadratics are set in the form:
ax^2 + bx + c = 0

where a and b and c are a certain value.

now the quadratic equation is

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

all you have to do is plug in whatever number is in your particular equation into the formula. an example is:

-x^2 + x + 1 = 0

in this a is -1 and b and c are 1
so:

(1 + or - sqrt (1^2 - 4 * (-1) * (1))) / (2 * -1)
(1 + or - sqrt (1 - (-4))) / -2
(1 + or - sqrt (5)) / -2

now we get 2 answers because of + or -

(1 + sqrt (5)) / -2 and (1 - sqrt (5)) / -2

Hello!
volume of sphere =4/3.pi.r^3