If two signs are sitting beside each other. FIX the notation before going on.
+ (- 3) becomes - 3 + (+ 3) becomes + 3+ in front of ( ) means to COMBINE what is inside So really, JUST ERASE IT and the ( )!
- (- 3) becomes + 3- in front of ( ) means to COMBINE the OPPOSITE of what is inside
Just change the second sign to its OPPOSITE then ERASE the first sign and the ( )!
VIEW ANIMATION for Step 1
Step 2 Determine if the signs of the numbers are the same or different.
To determine the sign of a number, look immediately in front of that number.
If there is a negative sign, the number is negative.
If there is a positive sign, the number is positive.
If there is no sign, the number is understood to be positive.
When comparing two numbers if they both
are negative or they both are positive,
they have the SAME sign.
When comparing two numbers if one is positive and one is
negative,
they have DIFFERENT signs.
VIEW ANIMATION for Step 2
Step 3 Follow the memorized rules for combining signed numbers.
These rules must be memorized and used faithfully.
Say them to yourself every time you combine signed numbers.
| If the numbers to be combined have ... | |
the SAME sign: |
add the numbers and keep the sign |
DIFFERENT signs: |
subtract the numbers and keep the sign of the larger* |
* the number that is larger if the signs are ignored |
VIEW ANIMATION for Step 3
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