Transcript 8.23 - msdiehl7math

ON A
SEPARATE
SHEET OF
PAPER!!
Do Now August
rd
23
• Find the absolute value.
1. |11| = _________
6. |-24| + 33 = ________
2. |-15| = ________
7. 7 x |-4| = ________
3. |-4| - 2 = ________
8. |48| - 16 = ________
4. 3 x |-6| = _________
9. 40 / |-8| = ________
5. |25| / 5 = ________
10. |-489| = ________
Do Now August
• Find the absolute value.
1. |11| = 11
6. |-24| + 33 = 57
2. |-15| = 15
7. 7 x |-4| = 28
3. |-4| - 2 = 2
8. |48| - 16 = 32
4. 3 x |-6| = 18
9. 40 / |-8| = 5
5. |25| / 5 = 5
10. |-489| = 489
rd
23
When do you use
negative numbers?
How do I add negative numbers with a number
line?
1. Identify starting point
2. Determine if you’re adding or subtracting
3. Does that mean go left or right?
4. Count the number of spaces to the left or
right that you are told.
5. That’s your answer!
1.Identify starting point
2.Add or subtract?
-5+7=?
Starting Point
ADD!
3.Left or Right?
To the Right
4. How far to the right?
5.What’s the answer?
-5+7=? Positive 2
Let’s try some Together!
1.
-9+5=
2.
On January 1st, the temperature was at 8 degrees. By
noon, the temperature had fallen by 6 degrees. At the
end of the afternoon, the temperature finally rose 4
degrees. What is the temperature?
3.
7+ -10=
4.
Ms. Diehl started the class giving 7 tickets. Four kids
were behaved and on task and were given tickets too.
How many tickets were given out?
Uh oh! That doesn’t fit
on the number line!
Adding with hills and holes!
• Hill are positive
• Holes are negative
• Draw the number of
hills and holes needed.
• Match up as many hills
with holes as you can
• The left over is your
answer.
• 4 + -2
Try these!
• -10 + 4
• 9+2
• 3 + -5
So does everyone
draw hills/holes or
number lines every
time they need to add
integers?
No! There is a basic rule!
Situation
Both numbers
are positive!
Rule
Example
--Add the
2+5=7
absolute values
of the two
numbers
together.
--The answer
will be positive.
Situation
Both integers
are negative
Rule
Example
--Add the
(-7) + (-2) =
absolute values (7 + 2) = 9 ----- -9
of the two
numbers
together.
--The answer
will be
negative.
Situation
Rule
One number is
positive and one
number is
negative
--Subtract the
8 + (-3) = 5
absolute value of
the smaller
number from the
absolute value of
the larger number.
--The sign of the
larger number is
the sign of the
answer
Example
Try a couple of these…
•The Tennessee Titans gained 12
yards in their first play. Their second
play was not as lucky, so they only
gained 5 yards. During their 3rd play,
they lost 6 yards. How many yards
did they end up with?
•-5 + -4 =
•-10 + 3 =
Stop and Jot
Take 3 minutes to write down your answer to the
following question. (Do this on the same paper you are
doing the “Do Now” and class work
This will be collected as a class work and participation
grade for today.
Which method (number line, hills and holes, or the rule)
helps you add integers the most? Why? Use that
favorite method to show:
-7 +8=
War!
• Black Cards are negative
• Red cards are positive
• Jack = 11
• Queen = 12
• King = 13
• Ace = 14
• Joker = 15
1. Each person flips over two cards
at a time.
2. Add the cards you have.
3. Whomever has the biggest
number wins and collects the pile of
cards.
4. You must write your problem in the
first box, work in the second, and
answer in the third. YOU MUST
RECORD EACH TIME!
5. Your goal is to collect all the cards
in the stack.
6. Play 3 games.
GAME TIME!
Two groups from yesterday join to make one
large group of 4.
If you were a group of 3 stay put and don’t join
with anyone.
1 Deck of cards per team. Divide the deck of
cards evenly between members.
4 team members = 13 each
3 team members = 17 or 18 each