Learn English – How to read “1 + (-2) = -1” and “1 – 2 = -1”

mathematicsreading-aloud

How to read this to others, so they can write it down just by listening?

1 + (-2) = -1

Also:

1 – 2 = -1

I want to know the differences.

Best Answer

How you explain this really depends on how much you want to convey, and how much you think will be assumed. For instance, the most specific wording of the first example would go something like this:

One plus open parenthesis negative two close parenthesis equals negative one.

The second example would be as follows:

One minus two equals negative one.

The important difference (pun intended) is how to say the '-' sign. I have found, contrary to the other answers so far, that a '-' when used on only one number (such as on the right side of those equations) is referred to as a 'negative' operator, whereas when used on two numbers it's a 'minus' sign. Saying 'two plus minus one', to me, implies 'plus or minus', which might not apply in most contexts but is definitely worth avoiding. On the other hand, 'two plus negative one' is immediately clear to me.

This even makes the parentheses in your first example unnecessary, and you can just say

One plus negative two equals negative one.

Unless you actually want everyone to write down the parentheses, in which case you should be explicit.

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