# How do you simplify 3r^2+ -8+ -10r^2+ -4r-r?

Nov 11, 2016

$- 7 {r}^{2} - 5 r - 8$

#### Explanation:

Step 1 is to group like terms and then combine like terms:

$3 {r}^{2} + - 8 + - 10 {r}^{2} + - 4 r - r \implies$

$\left(3 {r}^{2} + - 10 {r}^{2}\right) + \left(- 4 r - r\right) + - 8 \implies$

$\left(3 + - 10\right) {r}^{2} + \left(- 4 - 1\right) r + - 8$

$- 7 {r}^{2} + - 5 r + - 8 \implies$

$- 7 {r}^{2} - 5 r - 8$