# How do you solve x^2-10x+15=0 using the quadratic formula?

Apr 7, 2018

color(green)(x_+ = 5 + sqrt10), color(indigo)(x_- = 5 - sqrt10

#### Explanation:

$\text{Given equation is } {x}^{2} - 10 x + 15 = 0$

$a = 1 , b = - 10 , c = 15$

$x = \frac{- \left(- 10\right) \pm \sqrt{{\left(- 10\right)}^{2} - \left(4 \cdot 1 \cdot 15\right)}}{2}$
$x = \frac{10 \pm \sqrt{40}}{2}$
$x = \frac{10 \pm 2 \sqrt{10}}{2} = 5 \pm \sqrt{10}$
${x}_{+} = 5 + \sqrt{10} , {x}_{-} = 5 - \sqrt{10}$