Adding and Subtracting Directed Numbers Projector Resources Adding

Adding and Subtracting Directed Numbers Projector Resources Adding and Subtracting Directed Numbers

Why is this ‘ 4’? 4 Projector Resources Adding and Subtracting Directed Numbers P-1

How much is this? Projector Resources Adding and Subtracting Directed Numbers P-2

How much is this? 3 Projector Resources Adding and Subtracting Directed Numbers P-3

Making 3 Show me three more ways of making 3. Can you do one using 11 charges altogether? Projector Resources Adding and Subtracting Directed Numbers P-4

How much is this? Projector Resources Adding and Subtracting Directed Numbers P-5

How much is this? – 2 Projector Resources Adding and Subtracting Directed Numbers P-6

How much is this? Projector Resources Adding and Subtracting Directed Numbers P-7

How much is this? 0 Projector Resources Adding and Subtracting Directed Numbers P-8

How much is this? Projector Resources Adding and Subtracting Directed Numbers P-9

How much is this? +3 Projector Resources Adding and Subtracting Directed Numbers P-10

How would you describe what happens here? Projector Resources Adding and Subtracting Directed Numbers P-11

How would you describe what happens here? Projector Resources Adding and Subtracting Directed Numbers P-12

How would you describe what happens here? (+4) + Projector Resources Adding and Subtracting Directed Numbers P-13

How would you describe what happens here? (+4) + (– 2) = Projector Resources Adding and Subtracting Directed Numbers P-14

How would you describe what happens here? (+4) + (– 2) = (+2) Projector Resources Adding and Subtracting Directed Numbers P-15

How would you describe what happens here? +2 Projector Resources Adding and Subtracting Directed Numbers P-16

How would you describe what happens here? What do we get when we take away a negative? Projector Resources Adding and Subtracting Directed Numbers P-17

How would you describe what happens here? (+2) – Projector Resources Adding and Subtracting Directed Numbers P-18

How would you describe what happens here? (+2) – (– 1) = Projector Resources Adding and Subtracting Directed Numbers P-19

How would you describe what happens here? (+2) – (– 1) = (+3) Projector Resources Adding and Subtracting Directed Numbers P-20

What’s the story here? Projector Resources Adding and Subtracting Directed Numbers P-21

What’s the answer? 1 – (– 2) = Projector Resources Adding and Subtracting Directed Numbers P-22

What’s the answer? 1 – (– 2) = 3 Projector Resources Adding and Subtracting Directed Numbers P-23

Working Together 1 1. Choose one of the three cards and match it with one of the calculations. 2. Write the answer to the calculation after the equals sign. 3. Check that the answer matches what you see in the drawing. 4. Do the same with the other two cards. 5. Make up drawings to fit the remaining three calculations and write down the answers to those three calculations. 6. The answers should match the drawings. 7. Everyone in the group should agree. Projector Resources Adding and Subtracting Directed Numbers P-24

Calculations (1) Projector Resources Adding and Subtracting Directed Numbers P-25

How can I draw (+2) – (+5)? Projector Resources Adding and Subtracting Directed Numbers P-26

How can I draw (+2) – (+5)? Another way of thinking of (+2)… Projector Resources Adding and Subtracting Directed Numbers P-27

How can I draw (+2) – (+5)? And another… Projector Resources Adding and Subtracting Directed Numbers P-28

How can I draw (+2) – (+5)? And another… Do you agree that this is still (+2)? Projector Resources Adding and Subtracting Directed Numbers P-29

How can I draw (+2) – (+5)? And another… How can I take away (+5)? Projector Resources Adding and Subtracting Directed Numbers P-30

How can I draw (+2) – (+5)? And another… (+2) – (+5) = Projector Resources Adding and Subtracting Directed Numbers P-31

How can I draw (+2) – (+5)? And another… (+2) – (+5) = (– 3) Projector Resources Adding and Subtracting Directed Numbers P-32

Working Together 2 1. Choose one of the three cards and match it with one of the calculations. 2. Write the answer to the calculation after the equals sign. 3. Check that the answer matches what you see in the drawing. 4. Do the same with the other two cards. 5. Make up drawings to fit the remaining three calculations and write down the answers to those three calculations. 6. The answers should match the drawings. 7. Everyone in the group should agree. Projector Resources Adding and Subtracting Directed Numbers P-33

Calculations (2) Projector Resources Adding and Subtracting Directed Numbers P-34