Question

Which of the following equations has the solution set {0}?

-14m - 7m + 1 = -7m + 1
-14m + 7m + 1 = -7m + 2
14m - 7m - 1 = -7m + 1

Answer 1

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)

Explanation:

Answer 2

the first one
-14m - 7m + 1= -7m + 1
-7m