[tex] \frac{t - 12}{2}  =  \frac{3t}{2}  - 3 \\  \frac{t - 12}{2}  =  \frac{3t}{2}  -  \frac{3 \times 2}{1 \times 2} \\  \frac{t - 12}{2}   =  \frac{3t}{2}  -  \frac{6}{2}  \\  \frac{t - 12}{2}  =  \frac{3t - 6}{2}  \\ t - 12 = 3t - 6 \\ 3t - t =  - 12 + 6 \\ 2t =  - 6 \\ t =  \frac{ - 6}{2}  \\ t =  - 3[/tex]
The answer is t = -3