lesson 2.8 - dividing integers
DESCRIPTION
Class Notes from section 2.8TRANSCRIPT
Five-Minute Check (over Lesson 2–7)
Main Idea
Key Concept: Dividing Integers with Different Signs
Example 1: Dividing Integers with Different Signs
Example 2: Dividing Integers with Different Signs
Key Concept: Divide Integers with the Same Sign
Example 3: Dividing Integers with the Same Sign
Example 4: Evaluate an Expression
Example 5: Real-World Example
Concept Summary: Operations with Integers
Dividing Integers with Different Signs
Find 51 ÷ (–3).
Answer: –17
51 ÷ (–3) = –17 The integers have different signs. The quotient is
negative.
1. A
2. B
3. C
4. D0% 0%0%0%
A. –4
B. 4
C. 27
D. 45
Find 36 ÷ (–9).
Dividing Integers with Different Signs
Answer: –11
The integers have different signs. The quotient is
negative.
Find
1. A
2. B
3. C
4. D0% 0%0%0%
A. –5
B. 5
C. 36
D. 54
Dividing Integers with Same Sign
Find –12 ÷ (–2).
Answer: 6
–12 ÷ (–2) = 6 The integers have the same sign. The quotient is
positive.
1. A
2. B
3. C
4. D0% 0%0%0%
A. –32
B. –16
C. –3
D. 3
Find –24 ÷ (–8).
ALGEBRA Evaluate –18 ÷ x if x = –2.
Answer: 9
Evaluate an Expression
–18 ÷ x = –18 ÷ (–2) Replace x with –2.
= 9 Divide. The quotient is positive.
1. A
2. B
3. C
4. D0% 0%0%0%
A. –63
B. 63
C. 7
D. –7
ALGEBRA Evaluate g ÷ h if g = 21 and h = –3.
PHYSICS You can find an object’s acceleration
with the expression , where Sf = final speed,
Ss = starting speed, and t = time. If a car was
traveling at 80 feet per second and, after
10 seconds, is traveling at 40 feet per second, what
was its acceleration?
Answer: The car’s acceleration is –4 feet per second squared.
= –4 Divide.
Replace Sf with 40, Ss with 80, and t with 10.
Subtract 80 from 40
1. A
2. B
3. C
4. D
0% 0%0%0%
A. –20ºF
B. –4ºF
C. 12ºF
D. 4ºF
WEATHER The temperature at 4:00 P.M. was 52ºF. By 8:00 P.M., the temperature had gone down to 36ºF. What is the average change in temperature per hour?
End of the Lesson
Pg 117, # 10-30 evens, 32-37all, 39
Five-Minute Check (over Lesson 2–7)
Image Bank
Math Tools
Adding Integers
Comparing and Ordering Integers
Subtracting Positive and Negative Integers
1. A
2. B
3. C
4. D
A. $40,000
B. $36,505
C. $42,500
D. $44,000
Solve the problem by looking for a pattern. Tonya gets a job that pays $35,000 per year. She is promised a $1,500 raise each year. At this rate, what will her salary be in 5 years?
(over Lesson 2-7)
1. A
2. B
3. C
4. D
0% 0%0%0%
(over Lesson 2-7)
A. 4 inches
B. 3 inches
C. 6 inches
D. 1.5 inches
Solve the problem by looking for a pattern. A ball that is dropped from the top of a building bounces 48 inches up the first bounce, 24 inches up the second bounce, and 12 inches up the third bounce. At this rate, who far up will the ball bounce on a fifth bounce?
1. A
2. B
3. C
4. D0% 0%0%0%
(over Lesson 2-7)
A. 576,000 beats
B. 9,600 beats
C. 1,152,000 beats
D. 288,000 beats
Solve the problem by looking for a pattern. Hummingbird wing-beats are about 80 per second. At this rate, how many times does a hummingbird beat its wings in 2 hours?
1. A
2. B
3. C
4. D
0% 0%0%0%
(over Lesson 2-7)
A. 3 hours
B. 4 hours
C. 4.5 hours
D. 3.75 hours
Kendra created a 5-day study schedule for her exams. The table shows the number of hours she studies in the first three days. If the pattern continues, how many hours will she study on the fifth day?
