Solve for a 18-6a=4a-4(a+3)

$18 - 6 a = 4 a - 4 (a + 3)$

Step 1

Since $a$ is on the right side of the equation, switch the sides so it is on the left side of the equation.

$4 a - 4 (a + 3) = 18 - 6 a$

Step 2

Simplify $4 a - 4 (a + 3)$ .

Simplify each term.

Apply the distributive property.

$4 a - 4 a - 4 \cdot 3 = 18 - 6 a$

Multiply $- 4$ by $3$ .

$4 a - 4 a - 12 = 18 - 6 a$

Simplify by adding terms.

Subtract $4 a$ from $4 a$ .

$0 - 12 = 18 - 6 a$

Subtract $12$ from $0$ .

$- 12 = 18 - 6 a$

Step 3

Since $a$ is on the right side of the equation, switch the sides so it is on the left side of the equation.

$18 - 6 a = - 12$

Step 4

Move all terms not containing $a$ to the right side of the equation.

Subtract $18$ from both sides of the equation.

$- 6 a = - 12 - 18$

Subtract $18$ from $- 12$ .

$- 6 a = - 30$

Step 5

Divide each term in $- 6 a = - 30$ by $- 6$ and simplify.

Divide each term in $- 6 a = - 30$ by $- 6$ .

$\frac{- 6 a}{- 6} = \frac{- 30}{- 6}$

Simplify the left side.

Cancel the common factor of $- 6$ .

Cancel the common factor.

$\frac{- 6 a}{- 6} = \frac{- 30}{- 6}$

Divide $a$ by $1$ .

$a = \frac{- 30}{- 6}$

Simplify the right side.

Divide $- 30$ by $- 6$ .

$a = 5$