11-7 dividing integers warm up warm up lesson presentation lesson presentation problem of the day...
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11-7 Dividing Integers
Warm UpWarm Up
Lesson PresentationLesson Presentation
Problem of the DayProblem of the Day
Lesson QuizzesLesson Quizzes
11-7 Dividing Integers
Warm UpFind 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
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
11-7 Dividing Integers
Preview of MA.7.A.3.1 Use and justify the rules for…dividing…integers.
Preview of MA.7.A.3.2 Divide…integers,…including solving problems in everyday contexts.
Sunshine State Standards
11-7 Dividing Integers
Multiplication and division are inverse operations. To solve a division problem, think of the related multiplication.
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.
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.
11-7 Dividing Integers
Dividing IntegersIf 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.
= 0 = 0014__ 0
–11 __
You cannot divide any integer by 0.
Because division is the inverse of multiplication, the rules for dividing integers are the same as the rules for multiplying integers.
11-7 Dividing Integers
Additional Example 2A: Evaluating Integer Expressions
Evaluate for each value of d.
d = 16
Write the expression.
= 16 ÷ 4 Substitute 16 for d.
= 4 The signs are the same, so the answer is positive.
d 4__
d 4__
16 4 __
11-7 Dividing Integers
Additional Example 2B: Evaluating Integer Expressions
Evaluate for each value of d.
d = –24
Write the expression.
= –24 ÷ 4 Substitute –24 for d.
= –6 The signs are different, so the answer is negative.
d 4__
d 4__
-24 4 ___
11-7 Dividing Integers
Additional Example 2C: Evaluating Integer Expressions
Evaluate for each value of d.
d = –12
Write the expression.
= –12 ÷ 4 Substitute –12 for d.
= –3 The signs are different, so the answer is negative.
d 4__
d 4__
-12 4 ___
11-7 Dividing Integers
Check It Out: Example 2A
Evaluate for each value of c.
c = –15
Write the expression.
= –15 ÷ 3 Substitute –15 for c.
= –5 The signs are different, so the answer is negative.
c 3__
c 3__
-15 3 ___
11-7 Dividing Integers
Check It Out: Example 2B
Evaluate for each value of c.
c = 12
Write the expression.
= 12 ÷ 3 Substitute 12 for c.
= 4
c 3__
c 3__
12 3 ___
The signs are the same, so the answer is positive.
11-7 Dividing Integers
Check It Out: Example 2C
Evaluate for each value of c.
c = 27
Write the expression.
= 27 ÷ 3 Substitute 27 for c.
= 9 The signs are the same, so the answer is positive.
c 3__
c 3__
27 3 __
11-7 Dividing Integers
Standard Lesson Quiz
Lesson Quizzes
Lesson Quiz for Student Response Systems
11-7 Dividing Integers
Lesson QuizFind 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
–3 5
8
x 4__
11-7 Dividing Integers
1. Find the quotient. 32 ÷ (–4)
A. –8
B. –28
C. –26
D. –128
Lesson Quiz for Student Response Systems
11-7 Dividing Integers
2. Find the quotient. –55 ÷ (–5)
A. 60
B. 11
C. –60
D. –11
Lesson Quiz for Student Response Systems
11-7 Dividing Integers
3. Evaluate z ÷ 5 for z = –45.
A. –9
B. –40
C. –50
D. –225
Lesson Quiz for Student Response Systems
11-7 Dividing Integers
4. Stacey has 1,500 grams of flour. She needs 275 grams of flour to bake a cake. How many whole cakes can she bake?
A. 3
B. 4
C. 5
D. 6
Lesson Quiz for Student Response Systems