Answer: m=6
Step-by-step explanation:
[tex]9+12m=6+15\left(m-1\right)[/tex]
[tex]6+15\left(m-1\right)=15m-9[/tex]
[tex]9+12m=15m-9[/tex]
subtract 9 on both sides
[tex]9+12m-9=15m-9-9[/tex]
[tex]12m=15m-18[/tex]
subtract 15m on both sides
[tex]12m-15m=15m-18-15m[/tex]
[tex]-3m=-18[/tex]
divide by -3 on both sides
[tex]\frac{-3m}{-3}=\frac{-18}{-3}[/tex]
since [tex]\frac{-a}{-b}=\frac{a}{b}[/tex]
[tex]\frac{-18}{-3}=6[/tex]
[tex]m=6[/tex]
