# Question #8b7e5

Jun 9, 2017

$a = 3$

#### Explanation:

We begin the problem by distributing the $3$ and $4$ into the parenthesis:

$6 a + 9 - 12 a + 24 = 15$

Combine like terms:

$- 6 a + 33 = 15$

Subtract $33$ from both sides:

$- 6 a + \cancel{33} - \cancel{33} = 15 - 33$

You are left with:

$- 6 a = - 18$

Divide both sides by $- 6$:

$\frac{- 6 a}{-} 6 = \frac{- 18}{-} 6$

$a = 3$