Question

How do you find the roots, real and imaginary, of `y=-3x^2 + -3x -4` using the quadratic formula?

Answer 1

`x = -1/2 +- (isqrt39)/6`

Explanation:

Use the quadratic formula in graphic form (Google, Yahoo, Bing):
`y = - 3x^2 - 3x - 4 = 0`
`D = d^2 = b^2 - 4ac = 9 - 48 = - 39` < 0 --> `d = +- isqrt39`
Since d < 0, there are 2 imaginary roots.
`x = -b/(2a) +- d/(2a) = 3/-6 +- isqrt39/6 = -1/2 +- (isqrt39)/6`