When finding the sum of two negative numbers, will the answer be negative, positive or sometimes negative/sometimes positive?
Aaron – The answer will always be negative.
Betty – The answer will always be positive.
Clint – It depends on the numbers, sometimes it will be positive but sometimes it will be negative.
I agree with Aaron/Betty/Clint because…
Opposites
Absolute value
Additive Inverse
Integers
Commutative Property
Unit Plan
Students will learn to…
Determine the signs when adding and subtracting integers..
Represent addition of positive and negative numbers using a number line.
What are the possible combinations of addition problems?
Positive + Positive
Positive + Negative
Negative + Positive
Negative + Negative
Fold your notecard in half.
Write the following problems in the designated area of your notecard.
Front Left
4 + 3
2 + 8
3 + 5
Front Right 4 + (-3)
2 +(- 8)
3 + (-5)
Back Left
-4 + 3
-2 + 8
-3 + 5
Back Right -4 + (-3)
-2 + (-8)
-3 + (-5)
Bring your note card and notebook
Bring a pencil
We will model each problem together.
Write the answers on your notecard.
Make sure to get your negative sign, if needed.
Stay to the right
Walk in a line
Respect other classes by being quiet.
When finding the sum of two negative numbers, will the answer be negative, positive or sometimes negative/sometimes positive?
Who do you agree with now? Explain
Anytime you add negatives, your answer is always negative.
Write the following prompts…
A positive + positive means my answer is…
A positive + negative means my answer is…
A negative + positive means my answer is…
A negative + negative means my answer is…
In order to get a first down in football, the offensive team must gain 10 yards. On their first two plays, the Bears gained 5 yards and then lost 5 yards. How many yards do they need to gain on the third play to get a first down?
Write the math sentence that describes this situation.
Justify your response using math terminology.
Normal Temperatures for January(F)
1) Order the High temperatures from least to greatest.
2) Order the Low temperatures from least to greatest.
3) Which city has the highest average temperature?
City High Low
Barrow, Alaska -8 -20
Bismarck, N. Dakota 21 -1
Caribou, Maine 19 0
Duluth, Minn. 18 -1
Omaha, Nebraska 32 13
Opposites, Zero Pairs, Additive Inverse
Represent addition on a number line
Football field
Homework
Commutative Property of Addition
Students will learn to…
Demonstrate understanding of Opposites, zero pairs and additive inverse.
Discover the rules for adding integers.
Blue whales swim to different areas of the ocean depending on the water temperature. One whale that was being tracked was swimming at 100 feet below sea level. As the water he was swimming in began to heat up, he moved down another 50 feet below sea level.
1) Write a math sentence that represents this scenario.
2) What is the blue whale’s depth?
3) The whale decided to return to sea level. Write a math sentence that shows the entire journey.
1) -100 + (-50 )
2) -150 ft.
3) -100 + (-50) + 150 = 0
Opposites, Zero Pairs, Additive Inverse
Representing addition on a number line.
Commutative Property
Quiz
Students will learn to…
Discover the rules for adding integers.
Discuss strategies for solving integers.
Your Goal:
Discover the rules for adding integers
The Process:
Analyze your notecards
Determine the rules for:
Adding integers with the same sign
Adding integers with the opposite sign
Which prompts are similar to each other?
1. A positive + positive means my answer is…
2. A positive + negative means my answer is…
3. A negative + positive means my answer is…
4. A negative + negative means my answer is…
4 + 3 = 7 4 + (-3) = 1 -4 + 3 = -1 -4 + (-3) = -7
2 + 8 = 10 2 + (-8) = -6 -2 + 8 = 6 -2 + (-8) = -10
3 + 5 = 8 3 + (-5) = -2 -3 + 5 = 2 -3 + (-5) = -8
Analyze the answers to the expressions.
1. When signs are the same…
2. When signs are opposite…
43
Rule: To find the value of 43 , multiple 4 x 4 x 4
When your group has finished, stand up.
Meet with another group that has stood up.
Groups should take turns reading their rules to each other.
If you agree, you may sit back down.
If you disagree, discuss and try to come to a consensus.
When adding integers with the same sign…
When adding integers with the opposite sign…
When adding integers with the same sign…
Add and keep the sign
When adding integers with the opposite sign…
Subtract, keep sign of number with largest absolute value (largest digit)
Number Line
Context Money
Football
Others?
Rules for adding integers
Which strategy works best for you? Why?
At least 1 paragraph…