Integer Rules Anchor Chart
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Integer Rules
Quick Guide for Adding & Subtracting
Positive (+) Negative (−)
1
Adding Integers
Look at the signs!
Same Signs (+) & (+) OR (−) & (−)
ADD & KEEP
Add the numbers. Keep their sign.
(+4) + (+3) = +7
Both positive
(−5) + (−2) = −7
Both negative
Rule: Same signs stick together!
Different Signs (+) & (−)
SUBTRACT & KEEP BIGGER
Subtract the numbers. Take the bigger number's sign.
(−8) + (+3) = −5
8 is bigger → (−)
(+9) + (−4) = +5
9 is bigger → (+)
Rule: The bigger number wins the sign!
2
Subtracting Integers (Keep - Change - Change)
Turn minus into plus!
1st KEEP Keep 1st number
2nd CHANGE Change (−) to (+)
3rd CHANGE Flip 2nd sign to opposite
Ex 1 (+4) − (+7) (+4) + (−7)
7 is bigger → (−) = −3
Ex 2 (−5) − (−8) (−5) + (+8)
8 is bigger → (+) = +3
Ex 3 (−3) − (+6) (−3) + (−6)
Same signs → keep (−) = −9
Quick 2-Step Check
Subtracting?
Use Keep - Change - Change to turn it into addition.
Adding?
Same signs: Add & keep. Different signs: Subtract & pick bigger.