1-6 Multiplying and Dividing Integers Course 3 Warm Up Warm Up Problem of the Day Problem of the Day Lesson Presentation Lesson Presentation

Warm Up Multiply or divide. Course Multiplying and Dividing Integers (8) 2. 6(12) (7)6.

Problem of the Day Complete the pyramid by filling in the missing numbers. Each number is the sum of the numbers in the two boxes below it. Course Multiplying and Dividing Integers –98 –7 –15 –4 –8 –32 4

Learn to multiply and divide integers. Course Multiplying and Dividing Integers

Insert Lesson Title Here Course Multiplying and Dividing Integers A positive number multiplied by an integer can be written as repeated addition. 3(–200) = –200 + (–200) + (–200) = –600 From what you know about adding and subtracting integers, you can see that a positive integer times a negative integer is negative.

Insert Lesson Title Here Course Multiplying and Dividing Integers You know that multiplying two positive integers together gives you a positive answer. Look for a pattern in the integer multiplication at right to understand the rules for multiplying two negative integers. 3(–200) = 2(–200) = 1(–200) = 0(–200) = –1(–200) = –2(–200) = –3(–200) = –600 – – The product of two negative integers is a positive integer.

Insert Lesson Title Here Course Multiplying and Dividing Integers MULTIPLYING AND DIVIDING TWO INTEGERS If the signs are the same, the sign of the answer is positive. If the signs are different, the sign of the answer is negative.

Course Multiplying and Dividing Integers Additional Example 1: Multiplying and Dividing Integers A. –6(4) B. –8(–5) = 40 = –24 Signs are different. Signs are the same. Answer is negative. Answer is positive. Multiply or divide.

Course Multiplying and Dividing Integers Additional Example 1: Multiplying and Dividing Integers C. = –9 Signs are different. Answer is negative. Multiply or divide. –18 2 D. = 5 Signs are the same. Answer is positive. –25 –5

Course Multiplying and Dividing Integers Check It Out: Example 1 A. 5(–2) B. –3(–2) = 6 = –10 Signs are different. Signs are the same. Answer is negative. Answer is positive. Multiply or divide.

Course Multiplying and Dividing Integers Check It Out: Example 1 C. = –8 Signs are different. Answer is negative. Multiply or divide. –24 3 D. = 6 Signs are the same. Answer is positive. –12 –2

Course Multiplying and Dividing Integers Order of Operations 1. Parentheses 2. Exponents 3. Multiply and divide from left to right. 4. Add and subtract from left to right. Remember!

Course Multiplying and Dividing Integers Additional Example 2: Using the Order of Operations with Integers A. 3(–6 – 12) = –54 = 3(–18) Subtract inside the parentheses. Think: The signs are different. The answer is negative. Simplify. B. –5(–5 + 2) = 15 = –5(–3) Subtract inside the parentheses. Think: The signs are the same. The answer is positive.

Course Multiplying and Dividing Integers Additional Example 2: Using the Order of Operations with Integers C. –2(14 – 5) = –18 = –2(9) Subtract inside the parentheses. Think: The signs are different. The answer is negative. Simplify.

Course Multiplying and Dividing Integers Check It Out: Example 2 A. 2(1 – 8) = –14 = 2(–7) Subtract inside the parentheses. Think: The signs are different. The answer is negative. Simplify. B. 4(–3 – 8) = –44 = 4(–11) Subtract inside the parentheses. Think: The signs are different. The answer is negative.

Course Multiplying and Dividing Integers Check It Out: Example 2 C. –3(6 – 9) = 9 = –3(–3) Subtract inside the parentheses. Think: The signs are the same. The answer is positive. Simplify.

Course Multiplying and Dividing Integers The order of operations can be used to find ordered pair solutions of integer equations. Substitute an integer value for one variable to find the value of the other variable in the ordered pair.

Course Multiplying and Dividing Integers Additional Example 3: Sports Application A golfer plays 5 holes. On 3 holes, he has a gain of 4 strokes each. On 2 holes, he has a loss of 4 strokes each. Each gain in strokes can be represented by a positive integer, and each loss can be represented by a negative integer. Find the total net change in strokes. 3(4) + 2(–4) = 4 = 12 + (–8) Add the losses to the gains. Multiply. Add. The golfer changed by a total gain of 4 strokes.

Course Multiplying and Dividing Integers Check It Out: Example 3 A golfer plays 9 holes. On 3 holes, he has a gain of 3 strokes each. On 4 holes, he has a loss of 3 strokes each. Each gain in strokes can be represented by a positive integer, and each loss can be represented by a negative integer. Find the total net change in strokes. 3(3) + 4(–3) = -3 = 9 + (–12) Add the losses to the gains. Multiply. Add. The golfer changed by a total loss of 3 strokes.

Lesson Quiz: Part I Insert Lesson Title Here Course Multiplying and Dividing Integers Multiply or Divide. 1. –8(4) 2. –32 6 –12(5) –10 Simplify. 3. –2(13 – 4) 4. 6(-5 – 3) – 18 – 48

Lesson Quiz: Part II Insert Lesson Title Here Course Multiplying and Dividing Integers 5. Evin completes 11 transactions in his bank account. In 6 transactions, he withdraws $10. in 5 transaction, he deposits $20. Find the total net change in dollars. $40