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I positively have negative feelings about this! are positive and negative “whole” numbers, and zero. …-7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7… Integers do not include fractions or decimals. When you think about it, integers are everywhere. They represent temperatures… and chemical compounds. They’re in bank statements… Date Withdraw 8/23 –$65 9/24 10/10 11/17 Deposit Balance $4,054 +$150 –$220 $4,204 $3,984 +$75 and golf scores. $4,059 When we multiply or divide integers, there are just a couple of rules we need to remember. Whenever we multiply two integers with “like” signs, the answer is always positive. (+) × (+) = + 𝟕 × 𝟑 = 𝟐𝟏 Whenever we multiply two integers with “like” signs, the answer is always positive. (−) × (−) = + −𝟓 × (−𝟐) = 𝟏𝟎 Whenever we multiply two integers with “unlike” signs, the answer is always negative. (+) × (−) = − 𝟖 × (−𝟐) = −𝟏𝟔 Whenever we multiply two integers with “unlike” signs, the answer is always negative. (−) × (+) = − −𝟔 × 𝟒 = −𝟐𝟒 Whenever we divide two integers with “like” signs, the answer is always positive. + ÷ + =+ 𝟏𝟔 ÷ 𝟒 = 𝟒 Whenever we divide two integers with “like” signs, the answer is always positive. (−) ÷ (−) = + −𝟏𝟐 ÷ (−𝟒) = 𝟑 Whenever we divide two integers with “unlike” signs, the answer is always negative. (+) ÷ (−) = − 𝟗 ÷ −𝟑 = −𝟑 Whenever we divide two integers with “unlike” signs, the answer is always negative. (−) ÷ (+) = − −𝟏𝟓 ÷ 𝟑 = −𝟓 What did you notice about the rules for multiplying and dividing integers? If you said they’re exactly the same, you’re right! Multiply or divide the following integers. 1) 𝟓 × −𝟔 = 2) −𝟏𝟐 ÷ −𝟒 = 3) −𝟏𝟎 × 𝟗 = 4) 𝟑𝟔 ÷ −𝟔 = 5) −𝟕 × −𝟓 6) −𝟖𝟖 ÷ 𝟏𝟏 = = Multiply or divide the following integers. 1) 𝟓 × −𝟔 = −𝟑𝟎 3) −𝟏𝟎 × 𝟗 = −𝟗𝟎 5) −𝟕 × −𝟓 = 𝟑𝟓 2) −𝟏𝟐 ÷ −𝟒 =𝟑 4) 𝟑𝟔 ÷ −𝟔 = −𝟔 6) −𝟖𝟖 ÷ 𝟏𝟏 = −𝟖 Here are some other ways that multiplying and dividing integers might appear: Multiplying with a raised dot or using parenthesis: −𝟐 𝟔 𝟖(−𝟑) (−𝟓)(−𝟏𝟏) Dividing with a fraction bar: 𝟏𝟐 → −𝟒 𝟏𝟐 ÷ (−𝟒) −𝟗 → −𝟑 −𝟗 ÷ (−𝟑) But what if I have to multiply or divide more than two integers at once? An expression with an even number of negative integers will always produce a positive answer. An expression with an odd number of negative integers will always produce a negative answer. Let’s take a look at a few examples! Example 1: −𝟐 × −𝟑 × 𝟒 × −𝟐 = −𝟒𝟖 Since there are 3 negative integers (an odd amount), the answer will be negative. Then, multiply from left to right to find the product. Perform the above calculation as instructed to check the answer given. Example 2: −𝟑𝟐 ÷ 𝟐 ÷ 𝟒 ÷ −𝟐 = 𝟐 2 negative integers (an even amount) result in a positive quotient. Divide from left to right to simplify. Perform the above calculation as instructed to check the answer given. Example 3: 𝟐𝟓 ÷ (−𝟓) × 𝟒 ÷ −𝟒 × (−𝟐) × (−𝟕) = 𝟕𝟎 4 negative integers produce a positive answer. Multiply and divide from left to right to simplify. Perform the above calculation as instructed to check the answer given. So, I just count negative signs to determine the sign of my answer? Then I just multiply or divide from left to right? That’s it! An even number of negative signs equals a positive answer, and an odd number equals a negative answer. Multiply and/or divide. 1) −𝟔 ÷ 𝟐 × 𝟕 2) −𝟒 × −𝟔 ÷ (−𝟐) = = 3) 𝟐𝟎 ÷ (−𝟒) × 𝟐 × 𝟖 ÷ (−𝟒) = 4) −𝟏 × −𝟑 × 𝟏𝟎 ÷ (−𝟐) ÷ (−𝟑) = 5) −𝟔 ÷ −𝟑 × 𝟕 ÷ (−𝟕) × (−𝟐𝟎) ÷ (−𝟖) = Multiply and/or divide. 1) −𝟔 ÷ 𝟐 × 𝟕 2) −𝟒 × −𝟔 ÷ (−𝟐) = −𝟐𝟏 = −𝟏𝟐 3) 𝟐𝟎 ÷ (−𝟒) × 𝟐 × 𝟖 ÷ (−𝟒) = 𝟐𝟎 4) −𝟏 × −𝟑 × 𝟏𝟎 ÷ (−𝟐) ÷ (−𝟑) =𝟓 5) −𝟔 ÷ −𝟑 × 𝟕 ÷ (−𝟕) × (−𝟐𝟎) ÷ (−𝟖) = −𝟓 Get the booklet from your teacher and continue your practice The end