Solve for a 4a-4=8+a

$4 a - 4 = 8 + a$

Move all terms containing $a$ to the left side of the equation.

Subtract $a$ from both sides of the equation.

$4 a - 4 - a = 8$

Subtract $a$ from $4 a$ .

$3 a - 4 = 8$

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

Add $4$ to both sides of the equation.

$3 a = 8 + 4$

Add $8$ and $4$ .

$3 a = 12$

Divide each term in $3 a = 12$ by $3$ and simplify.

Divide each term in $3 a = 12$ by $3$ .

$\frac{3 a}{3} = \frac{12}{3}$

Simplify the left side.

Cancel the common factor of $3$ .

Cancel the common factor.

$\frac{3 a}{3} = \frac{12}{3}$

Divide $a$ by $1$ .

$a = \frac{12}{3}$

Simplify the right side.

Divide $12$ by $3$ .

$a = 4$