Can anyone help me with this question, i've been trying to work it out for 15 minutes now...

-6a²  bc - 12c + 3bcb     take out the greatest common factor = -3c

-3c ( 2a^2 + 4 - bd)

And that's all we can do.......!!!!   

[ If we knew the valuable of all the variables, we could just evaluate the original expression ]

THANK YOUUU!!!