Numbers Can be Positive or Negative
Table of Contents
No Sign Means Positive
If a number has no sign it usually means that it is a positive number.
Adding a Positive Number
Adding positive numbers is just simple addition.
Subtracting A Positive Number
Subtracting positive numbers is just simple subtraction.
Adding A Negative Number
Subtracting a positive is the same as adding a negative.
So these have the same result:
Subtracting A Negative Number
Subtracting a Negative is the same as adding!
Two Negatives make a Positive
It can all be put into 2 rules:
|2 same signs become a positive sign||+||4 + (+3) = 4 + 3 = 7|
3−(−6) = 3 + 6 = 9
|2 different signs become a negative sign||–||7 + (-4) = 7 – 4 = 3|
9−(+5) = 9 – 5 = 4
So, all you have to remember is:
- 2 same signs become a positive sign
- 2 different signs become a negative sign