Answer
$x = -8$ or $x = -12$
Work Step by Step
Divide each side by $3$ to obtain:
$$|x + 10| = 2$$
Use the definition $|x|=a \longrightarrow x=-a \quad \text{or} \quad x=a$ to obtain::
$$x + 10 = 2\quad \text{or} \quad x + 10 = -2$$
Solve the first equation first. Subtract $10$ from each side to isolate the constants to one side and the variable to the other:
$$x = -8$$
Solve the other equation. We subtract $10$ from each side to isolate the constants to one side and the variable to the other:
$$x = -12$$
Check for extraneous solutions.
Plug $x = -8$ into the original equation:
$$3|-8 + 10| = 6\\
3|2| = 6\\
3(2)=6\\
6=6$$
This statement is true; therefore, $-8$ is a solution of this equation.
Substitute $-12$ for $x$:
$$3|-12 + 10| = 6\\
3|-2| = 6\\
3(2)=6
6=6$$
This statement is true; therefore, $-12$ is a solution of this equation.
