Do Now 9/17/09Do Now 9/17/09

Take out HW from last night.Take out HW from last night. Textbook page 32 #14-40 even, #48-58 evenTextbook page 32 #14-40 even, #48-58 even

Copy HW in your planner.Copy HW in your planner. Text page 36, #12-30 evens, #36-46 evenText page 36, #12-30 evens, #36-46 even Quiz on integer addition and subtraction Monday.Quiz on integer addition and subtraction Monday.

In your journal, define the word SUBTRACT. In your journal, define the word SUBTRACT. Explain how you subtract two numbers.Explain how you subtract two numbers.

HomeworkHomework Textbook page 32 #14-40 even, #48-58 even Textbook page 32 #14-40 even, #48-58 even

14) A14) A 16) 916) 9 18) 1018) 10 20) -1320) -13 22) 322) 3 24) -1424) -14 26) 5026) 50 28) -1528) -15 30) 1330) 13 32) 2132) 21

34) -7134) -71 36) -436) -4 38) -138) -1 40) a) 2; b) -3; c) -1; d) Game 140) a) 2; b) -3; c) -1; d) Game 1 48) 1048) 10 50) -250) -2 52) -1852) -18 54) even54) even 56) odd56) odd 58) 758) 7

ObjectiveObjective

SWBAT subtract integers SWBAT subtract integers

Section 1.6 Section 1.6 “Subtracting Integers” “Subtracting Integers”

When subtracting two integers, When subtracting two integers, ADD ADD the OPPOSITEthe OPPOSITE of the second of the second number to the first. number to the first.

8 – 5 = 8 – 5 =

Instead of subtracting ADD Instead of subtracting ADD the OPPOSITE!! the OPPOSITE!!

What is the opposite of 5? What is the opposite of 5?

8 8 + (-5)+ (-5) = =

- 5 - 5

ADD the OPPOSITE ADD the OPPOSITE

33Do the “OPP-OPP”Do the “OPP-OPP”““Opposite-Opposite”Opposite-Opposite”

Don’t Subtract…Don’t Subtract…ADD the OPPOSITE!!!ADD the OPPOSITE!!!

-8 – 6 -8 – 6 Instead of subtracting ADD Instead of subtracting ADD the OPPOSITE!!the OPPOSITE!!

What is the opposite of 6? What is the opposite of 6? - 6 - 6

-8 -8 + (-6)+ (-6) = =ADD the OPPOSITEADD the OPPOSITE “OPP-OPP”“OPP-OPP”

-14-14

SubtractionSubtractionUsing a Number LineUsing a Number Line

00 11 22 33 44 55-1-1-2-2-3-3-4-4-5-5

When you ADD a POSITIVE NUMBER

-1 – (-5) = -1 – (-5) = +5

-1 + 5 = 4 -1 + 5 = 4 -1 -1 + (+5)+ (+5) = =

“OPP-OPP”

SubtractionSubtractionUsing a Number LineUsing a Number Line

00 11 22 33 44 55-1-1-2-2-3-3-4-4-5-5

When you ADD a NEGATIVE NUMBER2 – 7 = 2 – 7 =

-7

2 + (-7) = -5 2 + (-7) = -5 2 2 + (-7)+ (-7) = = “OPP-OPP”

Try It Out!!Try It Out!!

1). -8 – 21). -8 – 2

2). 2). -2 – 5-2 – 5

3). 3). 6 – (-5)6 – (-5)

4). 4). ||-4| – (-8) -4| – (-8)

-8 + (-2) = -10-8 + (-2) = -10

6 + (+5) = 116 + (+5) = 11

-2 + (-5) = -7-2 + (-5) = -7

4 + (+8) = 124 + (+8) = 12

17 – 3317 – 3317 + (-33)17 + (-33)

|17| = 17|17| = 17 |-33| = 33|-33| = 33

33 – 17 33 – 17 = 16 = 16 - - Because 33 has a greaterBecause 33 has a greaterabsolute value than 17 the absolute value than 17 the answer is “negative”.answer is “negative”.

““Add the Opposite”Add the Opposite”

|-83| = 83|-83| = 83-83 + (+25)-83 + (+25)

|25| = 25|25| = 25

83 – 25 83 – 25 = 58= 58--Because 83 has a greaterBecause 83 has a greaterabsolute value than 25 the absolute value than 25 the answer is “negative”.answer is “negative”.

|53| = 53|53| = 53

53 + (-85)53 + (-85)

|-85| = 85|-85| = 85

85 – 53 85 – 53 = 32= 32Because 85 has a greaterBecause 85 has a greaterabsolute value than 53 the absolute value than 53 the answer is “negative”.answer is “negative”.

-83 – (-25)-83 – (-25) ““Add the Opposite”Add the Opposite”

53 – 8553 – 85 ““Add the Opposite”Add the Opposite”

--

Negative or Positive?Negative or Positive? Without solving the problem, decide whether the Without solving the problem, decide whether the

sum will be positive, negative, or zero. (HINT: sum will be positive, negative, or zero. (HINT: write the problem as a sum).write the problem as a sum).

17 – (-2)17 – (-2)

positivepositive

-13 – 11-13 – 11

negativnegativee

-14 – (-14)-14 – (-14)

zerozero

73 – 84 73 – 84 negativenegative

17 + (+2)17 + (+2)

-13 + (-11)-13 + (-11)

-14 + (+14)-14 + (+14)

73 + (-84) 73 + (-84)

Add the Opposite !!!Add the Opposite !!!

Try It Out…Try It Out…

-43 – 95-43 – 95= -138= -138 -43 – (-15)-43 – (-15) = -28= -28

37 – (-46)37 – (-46)= 83= 83 -123 – 162-123 – 162 = -= -285285

13 – (-13)13 – (-13)= 26= 26 83 – 5783 – 57 = 26= 26

““Integer” CardsInteger” Cards““Integer” CardsInteger” Cards RedRed cards = Negative cards = Negative BlackBlack cards = Positivecards = Positive Jack = 11, Queen = 12, King =13Jack = 11, Queen = 12, King =13 Dealer deals each player 2 cards.Dealer deals each player 2 cards. The player with the The player with the higheshighest difference, t difference,

gets all the cards from that round. gets all the cards from that round. The player with the most cards at the end The player with the most cards at the end

of the deck wins!of the deck wins!

HomeworkHomework

Text page 36, #12-30 evens, #36-46 evenText page 36, #12-30 evens, #36-46 even