Integer RulesInteger Rules

Adding with the same Adding with the same signsign

• RulesRules• Add like normalAdd like normal• Keep the signKeep the sign

• ExamplesExamples-12 + -10 = -22 (all signs are negative)-12 + -10 = -22 (all signs are negative)12 + 10 = 22 (all signs are positive12 + 10 = 22 (all signs are positive

Adding with different Adding with different signssigns

• RulesRules• Subtract the difference of the Subtract the difference of the

absolute value (av)absolute value (av)• Keep the sign of the highest Keep the sign of the highest

absolute value (av)absolute value (av)

• ExamplesExamples-10 + 8-10 + 810 – 8 (subtract av)10 – 8 (subtract av)-2 (keep sign of highest av)-2 (keep sign of highest av)

Subtraction with Subtraction with different signsdifferent signs

• RuleRuleAdd the oppositeAdd the opposite

• Example Example 12 - (-12) =12 - (-12) =

12 + 12 = 24 (add the opposite of -12)12 + 12 = 24 (add the opposite of -12)

12 – (12) 12 – (12)

12 + (-12) = 0 (add the opposite of 12)12 + (-12) = 0 (add the opposite of 12)

Multiplication & division Multiplication & division (even number of signs)(even number of signs)

• RuleRule• If you multiply or divide integers that have If you multiply or divide integers that have

an even number of negative signs – then an even number of negative signs – then positivepositive

• ExamplesExamples-5 x -7 = 35 (even number of negative signs - 2)-5 x -7 = 35 (even number of negative signs - 2)

-2 x -3 x -2 x -1 = 12 (even number of negative -2 x -3 x -2 x -1 = 12 (even number of negative signs – 4)signs – 4)

-3 x 2 x -1 x 2 = 12 (even number of negative signs -3 x 2 x -1 x 2 = 12 (even number of negative signs – 2)– 2)

-20 / -5 = 4 (even number of signs – 2)-20 / -5 = 4 (even number of signs – 2)

Multiplication & divisionMultiplication & division(odd number of signs) (odd number of signs)

• RuleRuleIf you multiply or divide a integers that have an If you multiply or divide a integers that have an odd number of negative sings – then negativeodd number of negative sings – then negative

• ExamplesExamples-3 x 5 = -15 (odd number of negative signs – 1)-3 x 5 = -15 (odd number of negative signs – 1)

-3 x 4 x -2 x -1 = -24 (odd number of negative -3 x 4 x -2 x -1 = -24 (odd number of negative signs – 3)signs – 3)

12 / -3 = -4 (odd number of signs - 1)12 / -3 = -4 (odd number of signs - 1)

Additional practiceAdditional practice

• Integers Jeopardy – go to the Integers Jeopardy – go to the following linkfollowing link

http://www.math-play.com/Integers-Jeopardy/Integers-Jeopardy.html