2. Quick Start Expectations Fill in Learning Log: WS: 1-7 Practice (ODD only) * 30 mins this week of MathXLforSchool Warm Up: Write down three sets of examples of the commutative property using addition. Possible answers: 1,000 + 24 = 1,024 24 + 1,000 = 1,024 6.22 + 7.5 = 13.72 7.5 + 6.22 = 13.72 2 ½ + 3 ⅓ = 5 ⅚ 3 ⅓ + 2 ½ = 5 ⅚

3. What are the ABCDEs of Adding & Subtracting Positive & Negative Numbers? A: Addition. Add the Opposite: Make it an Addition problem. If it’s Subtraction, then Add the Opposite to make it Addition. B: Big Positive: Place a + sign in front of any positive number. Then place the bigger number first/on top, ready to subtract. C: Cover and Compare: Cover the operations and compare the signs of the two numbers. Different? DifferenceSame? Sum D: Do the Math: Subtract or Add, depending on different or same signs. But this isn’t the answer yet! E: Examine the Signs: Choose the sign from the bigger number. (The one you placed first/on top when doing the Math.) A: B: C: D: E:

4. Additive inverse Additive identity AN 2.2: How is a chip model or number line useful in finding an algorithm for Subtraction? Vocab Toolkit: Two numbers when added together equal Zero. (Opposites) 222 + ‾222 = 0 1/3 + ‾1/3 = 0 Adding Zero to any rational number results in a sum identical to the original number. 0 + 12.6 = 12.6 a + 0 = a

5. iPads: Learning Facilitators: Socrative Quiz Kahoot Quiz

7. Show Kim’s algorithm on your chip board:

8. Here’s another example: Otis earned $5 raking leaves. He wants to buy a used bike that costs $7. What number sentence would represent this? Let’s represent this using a chip board: His older sister puts 5 black chips on the table to represent the money Otis has. Show on your chip board: ⁺5 What is the value of Otis’s board? ⁺5 + ‾7 =

9. Show on your board how you would find a way to take away 7 His sister adds two black chips and two red chips. Is the value of the board still ⁺5 with the new chips added? Explain with a number sentence. Yes. ⁺5 + ⁺2 + ‾2 Otis’s sister asks, “How much more money do you need?” Otis replies, “I could find out by taking away $7. But I can’t take away $7 because there aren’t seven black chips on the board!” How does this help Otis find how much more he needs? He now has enough chips to take away 7 additive inverses

10. ⁺5 + ‾7 = ‾2 ⁺5 + ⁺2 + ‾2 + ‾7 = ‾2 Otis earned $5 raking leaves. He wants to buy a used bike that costs $7. How much money does he need? Or how much money is he short? After taking away ⁺7 on the chip board, what is left? ‾2 $2

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15. $40 He should use a negative sign, - $40.

16. Increase the score! -350 points Change a subtraction expression to addition by adding the opposite of the second number.

17. Change a subtraction expression to addition by adding the opposite of the second number. ‾500 + 150 = ‾350 ‾500 ─ ‾ 150 = ‾350 Don’t Subtract, Add the Opposite Then follow the Addition Rules