First, you'd solve the parenthesis, by multiplying the outside numbers with the ones on the inside. Then combine like terms on each sides. But, I solved this and it turns out that the answer would be 0, so....
8(c-9)=6(2c-12)-4c
8c-72=12c-72-4c
8c-72=8c-72
I mean they're equal I don't really know where to go from there. Hopefully I helped you out, even if it was a little bit.
