Integers Click on picture to begin What is an integer? An integer is a positive or negative whole number or zero.

Integers

Click on picture to begin

What is an integer?

• An integer is a positive or negative whole number or zero.

Examples of Integers

• TemperatureExample: The temperature increased 20 degrees.The integer is +20.

• MoneyExample: I lost $50 in the stock market.The integer is -50.

• Sea LevelExample: Southfield is 684 feet above sea level.The integer is +684.

Ordering Integers

• The numbers increase as you go right on the number line.• The numbers decrease as you go left on the number line.• Ordering integers example

increase

decrease

Integer Rules

Addition Rules

Subtraction Rules

Multiplication Rules

Division Rules

Additional Practice Web Resources

Addition Rules

• Positive + Positive

• Negative + Negative

• Positive + Negative &

Negative + Positive

Positive + Positive

-5-10

-15-20-25-30-35

+40+35

+30+25+20+10+5

0

+ = +

+

+

+

+

+

+

+

+

+

+ +

+

+

+ +

Examples1. 3 + 5 =82. 12 + 39 = 51 3. The initial temperature was 5 degrees.

If the temperature rises 20 degrees, what is the new temperature?5 + 20 = 25

Positive + Positive = Positive

Negative + Negative

-5-10

-15-20-25-30-35

+40+35

+30+25+20+10+5

0

+ = -

-

-

-

-

-

-

-

-

-

- -

-

-

- -

Examples1. (-5) + (-8) = -132. (-11) + (-89) = -1003. The initial temperature was -15 degrees.

If the temperature fell 10 degrees, what is the new temperature?(-15) + (-10) = -25

-

-

-

-

-

-

-

-

-

-

Negative + Negative = Negative

Positive + Negative & Negative + Positive

Positive + Negative = Negative + Positive =

Depends!• If the positive number is bigger, the answer

is positive.• If the negative number is bigger, the

answer is negative.• If they are same, they add up to zero.

HMM…

Positive + Negative & Negative + PositiveExamples1. (-4) + 3 = -1

+ =-

-

-

-

+

+

+

- +

+

+

-

-

-= -

2. 6 + (-2) = 4

+

+ +

+

+ +-

-+ =

+

+

+

+

+

+

-

-

=+

+ +

+

3. 4 + (-4) = 0

+

+ +

++

-

-

-

-=

+

+

+

+ -

-

-

- =

Subtraction Rules• Whenever you have a subtraction problem,

turn it into an addition problem by ADDING THE OPPOSITE. Then, use the addition rules.Examples1.5 - 3 = 5 + (-3) = 22.10 - 5 = 10 + (-5) = -53. -21 - 7 = (-21) + (-7) = -28 4. 8 - (-6) = 8 + 6 = 145. (-4) - (-2) = (-4) + 2 = -26. (-9) - (-9) = (-9) + 9 = 0

Multiplication Rules

• Positive x Positive

• Negative x Negative

• Positive x Negative &

Negative x Positive

Positive x Positive

x =

It’s a match, so that’s good (positive)!

Positive x Positive = Positive

Examples1. 5 x 3 = 152. 3 x 1 = 33. 13 x 13 = 1394. 9 x 8 = 72

Negative x Negative

x =

It’s a match, so that’s good (positive)!

Negative x Negative = Positive

Examples1. (-5) x (-3) = 152. (-3) x (-1) = 33. (-7) x (-8) = 564. (-10) x (-10) = 100

Positive x Negative & Negative x Positive

x =

It’s a not a match, so that’s bad (negative)!

Positive x Negative = Negative

Examples1. (-5) x 3 = -152. 3 x (-1) = -33. (-11) x 16 = -1764. 25 x (-5) = -125

Division Rules• Same rules as multiplication

Positive ÷ Positive = Positive Negative ÷ Negative = Positive Positive ÷ Negative = Negative Negative ÷ Positive = NegativeExamples

1. 6 ÷ 3 = 2 5. 6 ÷ (-3) = -2

2. 10 ÷ 4 = 4 6. (-19) ÷ 2 = -9

3. (-42) ÷ (-7) = 6 7. (-42) ÷ 7 = -6

4. (-16) ÷ (-3) = 5 8. 17 ÷ (-4) = -4€

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Additional Practice1. 5 + (-23) = 11. (-23) - (-23) =

2. (-8) x (-4) = 12. (-13) + 15 =

3. (-4) - 3 = 13. 13 x 6 =

4. 12 - 10 = 14. 85 + 122 =

5. 25 ÷ (-5) = 15. 99 ÷ (-99) =

6. (-14) + (-7) = 16. (-63) + 63 =

7. 3 x (-6) = 17. 8 - 30 =

8. (-11) ÷ 3 = 18. (-10) x 5 =

9. 54 ÷ 9 = 19. (-24) ÷ (-7) =

10. 12 x (-12) = 20. (-1) - 60 =

Additional Practice1. -18 11. 0

2. 32 12. 2

3. -7 13. 78

4. 2 14. 207

5. -5 15. -1

6. -21 16. 0

7. -18 17. -22

8. -3 18. -50

9. 6 19. 3

10. -144 20. -61

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Web Resources• McGraw-Hill Glencoe

http://www.glencoe.com/

• AAA Math

http://www.aaamath.com/