# How do you find the roots, real and imaginary, of y=(-2x-4)(x+1)+3x^2+4x  using the quadratic formula?

Apr 3, 2018

#### Answer:

$x = 2 \pm \sqrt{5}$

#### Explanation:

When expanded,

$y = {x}^{2} - 2 x - 4$

Using the quadratic formula,

$x = \frac{2 \pm \sqrt{4 + 16}}{2}$
$x = 2 \pm \frac{\sqrt{20}}{2}$
$x = 2 \pm \sqrt{5}$