# How do you solve x^2+2x-1=2 using the quadratic formula?

Jun 6, 2016

$x = 1$ or $x = - 3$

#### Explanation:

According to Quadratic formula the solution of a quadratic equation $a {x}^{2} + b x + c = 0$ is

$x = \frac{- b \pm \sqrt{{b}^{2} - 4 a c}}{2 a}$

As ${x}^{2} + 2 x - 1 = 2$

$\Leftrightarrow$ ${x}^{2} + 2 x - 3 = 0$, its solution is

$x = \frac{- 2 \pm \sqrt{{2}^{2} - 4 \times 1 \times \left(- 3\right)}}{2 \times 1}$

= $\frac{- 2 \pm \sqrt{4 + 12}}{2} = \frac{- 2 \pm \sqrt{16}}{2} = \frac{- 2 \pm 4}{2}$

Hence $x = 1$ or $x = - 3$