How do you find the zeros, real and imaginary, of y= -2x^2-12x-19 using the quadratic formula?

1 Answer
Jul 30, 2016

2 complex roots
x = - 3 +- isqrt2/2

Explanation:

y = - 2x^2 - 12x - 19 = 0
Use the new quadratic formula in graphic form (Socratic Search).
D = d^2 = b^2 - 4ac = 144 - 152 = - 8
Since D < 0, there are no real roots. There are 2 complex roots.
d = +- 2isqrt2
x = -b/(2a) +- d/(2a) = 12/-4 +- (2isqrt2)/4 = - 3 +- (isqrt2)/2