Apr 19, 2018

$7 r + 2$

#### Explanation:

A bracket indicates multiplying the separate items inside the brackets (those separated by a $+$ or $-$) with the number in front of the brackets.

Therefore, in the first set of brackets, you must multiply $r$ by $2$ $\left(2 r\right)$, $- 4$ by $2$ $\left(- 8\right)$. In the second set of brackets, you must multiply $r$ by $5$ $\left(5 r\right)$ and $2$ by $5$ $\left(10\right)$.

$2 r - 8 + 5 r + 10$

Then, you group like terms (the $r$'s together) and the constant numbers ($10$ and $- 8$) together;

$\implies 7 r + 2$