Step-by-step explanation:
[tex]\\ \:\:\:\:\sf {:}\dashrightarrow \dfrac{-2}{3m}=12[/tex]
[tex]\\ \:\:\:\:\sf {:}\dashrightarrow -2=3m\times 12[/tex]
[tex]\\ \:\:\:\:\sf {:}\dashrightarrow -2=6m[/tex]
[tex]\\ \:\:\:\:\sf {:}\dashrightarrow m=\dfrac{-2}{6}[/tex]
[tex]\\ \:\:\:\:\sf {:}\dashrightarrow{\underline{\boxed{\bf{ m=-\dfrac{1}{3}}}}}[/tex]
