# How do you use quadratic formula to solve 2x^2 + 4x + 2 = 0?

Jun 12, 2015

The solution for this equation is
 color(red)(x = -1

#### Explanation:

$2 {x}^{2} + 4 x + 2$
The equation is of the form color(blue)(ax^2+bx+c=0 where:
$a = 2 , b = 4 , c = 2$

The Discriminant is given by:
$\Delta = {b}^{2} - 4 \cdot a \cdot c$
$= {\left(4\right)}^{2} - \left(4 \cdot 2 \cdot 2\right)$
$= 16 - 16 = 0$
As $\Delta = 0$ then there is only one solution.

The solution is found using the formula
$x = \frac{- b \pm \sqrt{\Delta}}{2 \cdot a}$

As $\Delta = 0$, $x = \frac{\left(- 4\right) \pm \sqrt{0}}{2 \cdot 2} = - \frac{4}{4} = - 1$
So , $x = - 1$