Transcript Mini Lesson Integers and Number Line

Integers and Integer Operations
In terms of negative
and positive integers…
• What does it mean for someone to have 5
dollars in their pocket?
• Would those 5 dollars be negative or
positive?
• What does it mean for someone to owe
money?
• Would this amount of owed money be
positive or negative?
“Money Doesn’t Grow on Trees”
John owes $3, Virginia owes $5 but Alex doesn't
owe anything, in fact he has $3 in his pocket.
Place these people on the number line to find
who is poorest and who is richest.
Having money in your pocket is positive.
But owing money is negative.
So John has "-3", Virginia "-5" and Alex "+3"
Wind Chill Temperatures
You are working on a report about winter weather and you are
studying the wind-chill temperature. The wind-chill temperature is a
measure of how wind speed affects low temperatures and how the
combination of wind and low temperature feels to a human being.
You find a table of some wind-chill temperatures when the wind
speed is 5 miles per hour.
Actual
Temperature
(0F)
Wind-chill
Temperature
(0F)
15
10
5
0
-5
12
7
0
-5
-10
What is the effect that the wind has on the
actual temperature?
Actual
Temperature
(0F)
Wind-chill
Temperature
(0F)
15
10
5
0
-5
12
7
0
-5
-10
Plot the wind-chill temperatures
-10 -9 -8 -7 -6 -5 -4 -3 -2 -1
Actual
Temperature
(0F)
Wind-chill
Temperature
(0F)
0
1
2
3
4
5
6
7
8
9 10 11 12
15
10
5
0
-5
12
7
0
-5
-10
On a number line, the values of integers increase as
you move from left to right. Write the wind-chill
temperatures in order from least to greatest.
The wind chill temperature is 30F. When the wind speed is 15
miles per hour at the same
actual temperature, the wind
chill temperature is -90F. Which
wind chill temperature is
higher?
The wind chill temperature is -40F.
When the wind speed decreases to 5
miles per hour, the wind chill
temperature increases by 5 degrees.
What is the wind chill temperature
when the wind speed is 5 miles per
hour?
-10 -9 -8 -7 -6 -5 -4 -3 -2 -1
0
1
2
3
4
5
6
7
8
9 10 11 12
Addition
How could you use a number line to
add 4 and 7?
What does it mean to have 4 and 7?
Addition
How could you use a number
line to add -3 and 4?
What does it mean to have -3 and 4?
Addition
How could you use a number
line to add -2 and -5?
What does it mean to have -2 and -5?
Addition
How could you use a number
line to add -10 and 7?
What does it mean to have -10 and 7?
Addition
How could you use a number
line to add -8 and 6?
What does it mean to have -8 and 6?
Generally for Addition
On a number line, move to the ________ when
you add a positive integer.
Why?
On a number line, move to the ________ when
you add a negative integer.
Why?
Subtraction
How could you use a number line
to subtract 4 from 8?
What does it mean to subtract 4 from 8?
Subtraction
How could you use a number line
to subtract 5 from -3?
What does it mean to subtract 5 from -3?
Subtraction
How could you use a number line
to subtract-9 from -1?
What does it mean to subtract 4 from 8?
Subtraction
How could you use a number line
to subtract-4 from -6?
What does it mean to subtract -4 from -6?
Generally for Subtraction
On a number line, move to the ________
when you subtract a positive integer.
Why?
On a number line, move to the ________
when you subtract a negative integer.
Why?
Multiplication
How can we represent 3(5) without using
multiplication?
A. 3(5) = (5) + (5) + (5) = 15
Multiplication
How can we represent 3(-5) without using
multiplication?
B. 3(-5)= (-5) + (-5) + (-5)=
Multiplication
How can we represent 4(-2) without using
multiplication?
D. 4(-2) = ( ) + ( ) + ( ) + ( ) =
Multiplication
How can we represent 2(-1) without using
multiplication?
C. 2(-1) = (-1) + (-1) =
Division
Find each quotient by writing related multiplication
problem.
A. 48/6 = ? because 6 x ? = 48
B. 48/-6 = ? because -6 x ? = 48
C. -48/6 = ? because 6 x ? = -48
D. -48/ -6 = ? because -6 x ? = -48
?= _____
?= _____
?= _____
?= _____
Interactive Number Line
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