# How do you solve 5r ^ { 2} + 10r = 0?

Apr 28, 2018

$r = 0 \text{ " or" } r = - 2$

#### Explanation:

$5 {r}^{2} + 10 r = 0$

$5 r \left(r + 2\right) = 0$

$5 r = 0 \text{ or } \left(r + 2\right) = 0$

If $5 r = 0 , \text{ then, } r = 0$

If $\left(r + 2\right) = 0 , \text{ then, } r = - 2$