1 6 Multiplying and Dividing Integers Warm Up

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

1 -6 Multiplying and Dividing Integers Warm Up Multiply or divide. 1. 5(8) 36 3. 9 5. 18(7) Course 3 40 4 126 2. 6(12) 4. 49 7 6. 192 16 72 7 12

1 -6 Multiplying and Dividing Integers 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. – 4 – 8 4 – 7 2 Course 3 – 9 – 1 5 8 – 3

1 -6 Multiplying and Dividing Integers Learn to multiply and divide integers. Course 3

1 -6 Multiplying Insert Lesson Here. Integers and. Title Dividing A positive number multiplied by an integer can be written as repeated addition. 3(– 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. Course 3

1 -6 Multiplying Insert Lesson Here. Integers and. Title Dividing 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. Course 3 3(– 200) = – 600 2(– 200) = – 400 1(– 200) = – 200 0(– 200) = 0 + 200 – 1(– 200) = 200 The product of two negative – 2(– 200) = 400 integers is a positive integer. – 3(– 200) = 600

1 -6 Multiplying Insert Lesson Here. Integers and. Title Dividing 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 3

1 -6 Multiplying and Dividing Integers Additional Example 1: Multiplying and Dividing Integers Multiply or divide. A. – 6(4) = – 24 B. – 8(– 5) = 40 Course 3 Signs are different. Answer is negative. Signs are the same. Answer is positive.

1 -6 Multiplying and Dividing Integers Additional Example 1: Multiplying and Dividing Integers Multiply or divide. C. D. Course 3 – 18 2 Signs are different. = – 9 Answer is negative. – 25 – 5 Signs are the same. =5 Answer is positive.

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

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

1 -6 Multiplying and Dividing Integers Remember! Order of Operations 1. Parentheses 2. Exponents 3. Multiply and divide from left to right. 4. Add and subtract from left to right. Course 3

1 -6 Multiplying and Dividing Integers Additional Example 2: Using the Order of Operations with Integers Simplify. A. 3(– 6 – 12) Subtract inside the parentheses. = 3(– 18) Think: The signs are different. = – 54 The answer is negative. B. – 5(– 5 + 2) Subtract inside the parentheses. = – 5(– 3) Think: The signs are the same. = 15 The answer is positive. Course 3

1 -6 Multiplying and Dividing Integers Additional Example 2: Using the Order of Operations with Integers Simplify. C. – 2(14 – 5) Course 3 Subtract inside the parentheses. = – 2(9) Think: The signs are different. = – 18 The answer is negative.

1 -6 Multiplying and Dividing Integers Check It Out: Example 2 Simplify. A. 2(1 – 8) = 2(– 7) Think: The signs are different. = – 14 The answer is negative. B. 4(– 3 – 8) Course 3 Subtract inside the parentheses. = 4(– 11) Think: The signs are different. = – 44 The answer is negative.

1 -6 Multiplying and Dividing Integers Check It Out: Example 2 Simplify. C. – 3(6 – 9) Course 3 Subtract inside the parentheses. = – 3(– 3) Think: The signs are the same. =9 The answer is positive.

2 -3 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 3

1 -6 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) Add the losses to the gains. = 12 + (– 8) Multiply. =4 Add. The golfer changed by a total gain of 4 strokes. Course 3

1 -6 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) Add the losses to the gains. = 9 + (– 12) Multiply. = -3 Add. The golfer changed by a total loss of 3 strokes. Course 3

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

1 -6 Multiplying Insert Lesson and. Title Dividing Here. Integers Lesson Quiz: Part II 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 Course 3