Answer:
It would be the first one because the second one has a 2 and we know that the 2 does not cancel out the one. This leaving us with 2 answers left. The 3rd one is not the correct one, this is because when you subtract the 14m - 7m you get 7m - 1, then you would subtract the 7m and -7m because the ones canceled each other out. This leading us to get -14m and not a 0. This leaving the last one, which is the first one. This having to be the first one is correct.
(I did this on a test and got it right) (It's the first one)
Step-by-step explanation:
