c - 14 = 12 the goal here is to get c by itself on one side but you see c isn't by itself, its being subtracted by 14. To undo that we add 14, -14 + 14 = 0 but what you do to one side you must do to the other side.
c - 14 + 14 = 12 + 14
c -0 = 26 (c -0 is just c)
c = 6
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