Answer: D., 7m+14
Explanation: the right side has negative, so to cancel those numbers out you add the opposite to both sides. Add 2m to both sides, and combine like terms. That gives you 7m. Do the same with the 6, adding up to 14. Now, write out the equation to get 7m+14, which is the last answer, or D. These questions are always negative or positive sensitive. At first sight, you would solve for 3m+2 which would be wrong, because this question is meant to trick you. But yeah, the answer is 7m+14. Hope this helps. :)