Math basics › Numbers and fractions
Negative numbers
Multiplying and dividing
Two negatives give a positive, one negative gives a negative. Count the minus signs: even is positive, odd is negative.
Adding and subtracting
Subtracting a negative adds: 5 − (−3) = 8. Think of it as removing a debt.
The trap
The rules for × are not the rules for +. −2 + −3 is −5, not 5.