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.

Quick Start ExpectationsFill 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 = 1,02424 + 1,000 = 1,024

6.22 + 7.5 = 13.72 7.5 + 6.22 = 13.72

2 ½ + 3 ⅓ = 5 ⅚3 ⅓ + 2 ½ = 5 ⅚

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? Difference Same? SumD: 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:

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 = 12.6a + 0 = a

iPads: Learning Facilitators:

Socrative Quiz

Kahoot Quiz

Show Kim’s algorithm on your chip board:

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 =

Show on your board how you would find a way to take away 7His 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

⁺5 + ‾7 = ‾2

⁺5 + ⁺2 + ‾2 + ‾7 = ‾2Otis 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

‾

$40

He should use a negative sign, - $40.

Increase the score!

-350 points

Change a subtraction expression to addition by adding the opposite of the second number.

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