# How do you solve -18- 6k = 6( 1+ 3k )?

Oct 3, 2017

$k = - 1$

#### Explanation:

$\text{distribute the bracket on the right side}$

$- 18 - 6 k = 6 + 18 k$

$\text{collect terms in k on the left side and numeric values}$
$\text{on the right side}$

$\text{subtract 18k from both sides}$

$- 18 - 6 k - 18 k = 6 \cancel{+ 18 k} \cancel{- 18 k}$

$\Rightarrow - 18 - 24 k = 6$

$\text{add 18 to both sides}$

$\cancel{- 18} \cancel{+ 18} - 24 k = 6 + 18$

$\Rightarrow - 24 k = 24$

$\text{divide both sides by } - 24$

$\frac{\cancel{- 24} k}{\cancel{- 24}} = \frac{24}{- 24}$

$\Rightarrow k = - 1$

$\textcolor{b l u e}{\text{As a check}}$

Substitute this value into the equation and if both sides are equal then it is the solution.

$\text{left } = - 18 + 6 = - 12$

$\text{right } = 6 \left(1 - 3\right) = 6 \times - 2 = - 12$

$\Rightarrow k = - 1 \text{ is the solution}$