Download review: adding and subtracting integers

WARM UP
1. Complete the pattern and
2. Find the value of x if the
then give a brief description of Perimeter = 32 units
the pattern:
9
x+2
49, 36, 25, 16, ___, ___, ____
10
Description:________
4. You purchase a video game 5. Simplify the expression.
system for $150. You make a
down payment of $25. You pay
4–5+0–6
the rest of the money you owe
in 5 equal payments. How
much is each payment?
3. Solve for x. SHOW STEPS!!!
5x = - 25
6. What problems did you
miss and what were they
about? What were your
mistakes?
Setting up your binder:
• Take out your 3 inch binder.
• 5 tabs ( warm ups, homework, notes/vocabulary, classwork,
quizzes/tests.
• Put some loose leaf paper behind the warm up, homework
and notes tab.
• Put some graph paper behind the classwork and homework
tab.
• Put your single subject notebook behind the classwork tab.
REVIEW: ADDING AND SUBTRACTING INTEGERS
Think back to last year, and maybe even sixth grade when you were introduced
to integers. Take a few minutes and reflect on the following questions. Record
your answers in your notebook.
1. What is an integer?
2. Why do we need to know how to work with integers?
3. Write down a few examples of where we would use integers in everyday life.
4. Can you remember the rule that we use to apply to integer problems?
Let’s discuss some of the rules/strategies that you could use to work with
adding and subtracting integers.
Think/pair/share
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Have you heard of heaps and holes?
Working with your partner, use chips to model the following examples.
Record the answers.
Write a “story” using the numbers. (A real world situation)
Once you are done, come up with a sentence or two stating the rule for
adding and subtracting integers. Record your sentences in your classwork
book.
Be ready to share your answers with your group and eventually the class.
1. - 12 + 8
2. (- 3) – (- 2)
3. 8 + 5
4. - 5 – 7
In the notes section of your binder, record the following rules.
An integer is a whole number and its opposite: - 3; - 2; - 1; 0; 1; 2; 3
Positive integer – an integer that is greater than zero
Negative integer – an integer that is less than zero
Absolute value – the distance a number is from zero on a number line
Additive inverse – the opposite of an integer, the sum of an integer and its
additive inverse is zero ( - 5 + 5 ) = 0
Addition of Integers:
• When adding integers and the signs are the same, (both positive or both
negative) add the absolute values and use the same sign. Ex. - 4 - 8 = - 12
and 3 + 9 = 12
• When adding integers and the signs are different, subtract the absolute
values and use the sign of the number with the larger absolute value.
Ex. - 11 + 4 = - 7 and 12 + (- 6) = 6
Subtraction of Integers:
• To subtract an integer, add its opposite. Ex. ( -3) – (- 2) = - 1 and 3 – (- 4) = 7
Time to practice.
Each group will receive a pack of playing cards. Here are the rules to the game.
Spades and clubs = black = negative numbers
Diamonds and hearts = red = positive numbers
Deal the pack of cards between the two pairs.
Each pair will flip a card and add the numbers together.
The largest sum wins and will take the pair of cards and place them to the side.
Repeat the steps until time is called.
• The pair that has the most cards when time is called will be named winners.
• We will play this game a second time, but using subtraction rules.
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Ticket out the door………
Independently, on the index card that has been given to you,
record the following examples and their answers.
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2 + (- 4)
8+9
- 6 + (- 3)
- 7 – (- 6)
(- 9) - 4
Turn your card in for a grade. Is your NAME on your work?
Homework
You have been given a worksheet to practice adding and subtracting
integers.
Attempt to complete the worksheet. DO NOT spend more than 30
minutes on tonight’s homework.