Solve for x:
Use distributive property on the left hand side:
[tex]3x-12=-21[/tex]Add 12 to both sides:
[tex]\begin{gathered} 3x-12+12=-21+12 \\ 3x=-9 \\ \end{gathered}[/tex]Divide both sides by 3:
[tex]\begin{gathered} \frac{3x}{3}=-\frac{9}{3} \\ x=-3 \end{gathered}[/tex]Answer:
x = -3
