Multiplying and dividing integers
Multiply and divide integers using sign rules.
Objective
Multiply and divide integers using sign rules.
What it means
When multiplying or dividing two integers, like signs give a positive result and unlike signs give a negative result.
Key terms
- Like signs
- Both numbers positive or both negative.
- Unlike signs
- One number positive, one negative.
Rules to remember
- (+)×(+) = + and (-)×(-) = +
- (+)×(-) = - and (-)×(+) = -
- The same rules apply to division.
Step by step
- 1Multiply/divide magnitudesIgnore signs and compute with absolute values.
- 2Apply the sign ruleLike signs give positive, unlike signs give negative.
Common mistakes
- Assuming multiplying two negatives gives a negative.
- Losing track of the sign after several operations.
Tips
- Count the negative signs: an even count gives positive, odd gives negative.
- Compute magnitude first, then decide the sign.