# How do you simplify -3sqrt(7r^3)*6sqrt(7r^2)?

Dec 13, 2017

$= - 126 {r}^{2} \sqrt{r}$

#### Explanation:

You can combine the two square roots into one because they are being multiplied.

$- 3 \sqrt{7 {r}^{3}} \times 6 \sqrt{7 {r}^{2}}$

$= - 18 \sqrt{{7}^{2} {r}^{5}}$

$= - 18 \times 7 {r}^{2} \sqrt{r}$

$= - 126 {r}^{2} \sqrt{r}$