# How do you solve -3( 3- 2n ) + 7n = 3( n + 3)?

Mar 15, 2018

$n = 1.8$

#### Explanation:

$- 9 + 6 n + 7 n = 3 n + 9$

$- 9 + 13 n = 3 n + 9$

$- 18 = - 10 n$

$n = 1.8$

Mar 15, 2018

Re-arrange and reduce to find $n = 1.8$

#### Explanation:

First, add $3 \left(3 - 2 n\right)$ to both sides. This eliminates the $- 3 \left(3 - 2 n\right)$ from the Left-Hand Side (LHS)

$7 n = 3 \left(n + 3\right) + 3 \left(3 - 2 n\right)$

Since both sets of parentheses have the same coefficient, you can add the contents of the parentheses together without expanding:

$7 n = 3 \left(n + 3 + 3 - 2 n\right) \Rightarrow 7 n = 3 \left(6 - n\right)$

NOW we expand the parentheses, and move all of the $n$'s to the LHS:

$7 n = 18 - 3 n \Rightarrow 10 n = 18$

Finally, we divid through by $n$'s coefficient to find the value of $n$:

$n = \frac{18}{10} = 1.8$