11-7 Dividing Integers Warm Up Problem of the Day Lesson Presentation Course 1 Warm Up Problem of the Day Lesson Presentation

Dividing Integers 11-7 Warm Up Find each quotient. 1. 18 ÷ 2 2. 42 ÷ 7 Course 1 11-7 Dividing Integers Warm Up Find each quotient. 1. 18 ÷ 2 2. 42 ÷ 7 3. 56 ÷ 8 4. 24 ÷ 6 5. 3,600 ÷ 4 6. 540 ÷ 60 9 6 7 4 900 9

Dividing Integers 11-7 Problem of the Day Course 1 11-7 Dividing Integers Problem of the Day Hank wanted to record the number of marbles he lost to his friend Marcus each day for 5 days. He forgot to record one day, but for the other days he wrote 8, 2, 3, and 4. The average number he lost was 4. What number did he forget to write? 3

Course 1 11-7 Dividing Integers Learn to divide integers.

Course 1 11-7 Dividing Integers Multiplication and division are inverse operations. To solve a division problem, think of the related multiplication. To find the mean of a list of numbers: 1. Add all the numbers together. 2. Divide by how many numbers are in the list. Remember!

Additional Example 1: Dividing Integers Course 1 11-7 Dividing Integers Additional Example 1: Dividing Integers Find each quotient. A. –30 ÷ 6 B. –42 ÷ (–7) Think: What number times 6 equals –30? –5 • 6 = –30, so –30 ÷ 6 = –5. Think: What number times –7 equals –42? 6 • (–7) = –42, so –42 ÷ (–7) = 6.

Dividing Integers 11-7 Check It Out: Example 1 Find each quotient. Course 1 11-7 Dividing Integers Check It Out: Example 1 Find each quotient. A. –15 ÷ 5 B. –36 ÷ (–6) Think: What number times 5 equals –15? –3 • 5 = –15, so –15 ÷ 5 = –3. Think: What number times -6 equals –36? 6 • (–6) = –36, so –36 ÷ (–6) = 6.

Dividing Integers 11-7 Dividing Integers Course 1 11-7 Dividing Integers Because division is the inverse of multiplication, the rules for dividing integers are the same as the rules for multiplying integers. Dividing Integers If the signs are the same, the product is positive. 24 ÷ 3 = 8 –6 ÷ (–3) = 2 If the signs are different, the quotient is negative. –20 ÷ 5 = –4 72 ÷ (–8) = –9 Zero divided by any integer equals 0. 14 __ –11 __ = 0 = 0 You cannot divide any integer by 0.

Additional Example 2A: Evaluating Integer Expressions Course 1 11-7 Dividing Integers Additional Example 2A: Evaluating Integer Expressions Evaluate for each value of d. d = 16 d 4 __ d 4 __ Write the expression. 16 4 __ = 16 ÷ 4 Substitute 16 for d. = 4 The signs are the same, so the answer is positive.

Additional Example 2B: Evaluating Integer Expressions Course 1 11-7 Dividing Integers Additional Example 2B: Evaluating Integer Expressions Evaluate for each value of d. d = –24 d 4 __ d 4 __ Write the expression. -24 4 ___ = –24 ÷ 4 Substitute –24 for d. = –6 The signs are different, so the answer is negative.

Additional Example 2C: Evaluating Integer Expressions Course 1 11-7 Dividing Integers Additional Example 2C: Evaluating Integer Expressions Evaluate for each value of d. d = –12 d 4 __ d 4 __ Write the expression. -12 4 ___ = –12 ÷ 4 Substitute –12 for d. = –3 The signs are different, so the answer is negative.

Dividing Integers 11-7 Check It Out: Example 2A Course 1 11-7 Dividing Integers Check It Out: Example 2A Evaluate for each value of c. c = –15 c 3 __ c 3 __ Write the expression. -15 3 ___ = –15 ÷ 3 Substitute –15 for c. = –5 The signs are different, so the answer is negative.

Dividing Integers 11-7 Check It Out: Example 2B Course 1 11-7 Dividing Integers Check It Out: Example 2B Evaluate for each value of c. c = 12 c 3 __ c 3 __ Write the expression. 12 3 ___ = 12 ÷ 3 Substitute 12 for c. = 4 The signs are the same, so the answer is positive.

Dividing Integers 11-7 Check It Out: Example 2C Course 1 11-7 Dividing Integers Check It Out: Example 2C Evaluate for each value of c. c = 27 c 3 __ c 3 __ Write the expression. 27 3 __ = 27 ÷ 3 Substitute 27 for c. = 9 The signs are the same, so the answer is positive.

Insert Lesson Title Here Course 1 11-7 Dividing Integers Insert Lesson Title Here Lesson Quiz Find each quotient. 1. 18 ÷ (–3) 2. –36 ÷ (–6) 3. –64 ÷ (–8) 4. –45 ÷ 3 Evaluate for each value of x. 5. x = –12 6. x = 20 7. Carmen’s mom has $3,200 in her bank account. If she uses the money to make monthly rent payments of $375, how many whole payments can she make? –6 6 8 –15 x 4 __ –3 5 8