Math Test

Our class had a math test the other day. Some of the questions were 'Solving Equations using Addition.' For example if you have a question like: n + 2 = 15 you will automatically know n = 13, but to prove it you write the question like this:

n + 2 = 15

n + 2 + (-2) = 15 + (-2)

n = 13

That's how you prove that 'n' is equal to 13.