Resposta :
[tex]3x - 15 = 18 \\ [/tex]
[tex]3x = 18 + 15 \\ [/tex]
[tex]3x = 33 \\ [/tex]
[tex]x = \frac{33}{3} \\ [/tex]
[tex]\boxed{x = 11} \\ [/tex]
Att. YRZ
[tex]\large\boxed{\begin{array}{l} \tt 3x - 15 = 18 \\ \tt3x = 18 + 15 \\ \tt3x = 33 \\ \tt x = \dfrac{33}{3} \\ \\\tt x = 11\end{array}}[/tex]