MULTIPLYING RATIONAL NUMBERS IF THE SIGNS ARE THE SAME, MULTIPLY THEIR ABSOLUTE VALUES AND THE...

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MULTIPLYING RATIONAL NUMBERS

IF THE SIGNS ARE THE SAME, MULTIPLY THEIR ABSOLUTE VALUES

AND THE ANSWER IS POSITIVE.

(+4)(+5) =

(-4)(-5) =

(3)(6) =

(-10)(-4) =

SIGNS ARE THE SAME

THE ANSWER IS POSITIVE

20

20

18

40

MULTIPLYING RATIONAL NUMBERS

IF THE SIGNS ARE THE DIFFERENT, MULTIPLY THEIR ABSOLUTE VALUES

AND THE ANSWER IS NEGATIVE.

(+3)(-5) =

(-3)(+5) =

(7)(-2) =

(-20)(3) =

SIGNS ARE DIFFERENT

THE ANSWER IS NEGATIVE

-15

-15

-14

-60

MULTIPLYING RATIONAL NUMBERS

MULTIPLYING FRACTIONS

4

3

3

2

12

6

2

1

Multiply straight across

Reduce your answer

MULTIPLYING RATIONAL NUMBERS

MULTIPLYING FRACTIONS

11

6

4

7

44

42

22

21

Multiply straight across

Reduce your answer

MULTIPLYING RATIONAL NUMBERS

MULTIPLYING FRACTIONS

11

6

4

7

22

21

Reduce - Cancel

Multiply straight across

3

2

SECOND OPTION – REDUCE FIRST

MULTIPLYING RATIONAL NUMBERS

MULTIPLICATION PROPERTY OF -1

The product of any number and -1 is its additive inverse (opposite).

5(-1) = -5

-5(-1) = 5

-30(-1) = 30

MULTIPLYING RATIONAL NUMBERS

Evaluate 3xy + 2y if x = 3 & y = -2

3xy + 2y = 3(3)(-2) + 2(-2)

= 9(-2) + 2(-2)

= -18 + (-4)

= -22

DIVIDING RATIONAL NUMBERS

IF THE SIGNS ARE THE SAME, DIVIDE THEIR ABSOLUTE VALUES AND

THE ANSWER IS POSITIVE.

SAME RULES AS FOR MULTIPLICATION!

IF THE SIGNS ARE THE DIFFERENT, DIVIDE THEIR ABSOLUTE VALUES AND

THE ANSWER IS NEGATIVE.

(+6)÷(+3) = 2 (-6)÷(-3) = 2

(+6)÷(-3) = -2 (-6)÷(+3) = -2

DIVIDING RATIONAL NUMBERS

DIVIDING FRACTIONS

10

3

5

6

1

44

Invert and multiply (I.A.M.)

Reduce

3

10

5

62

1 1

2

Multiply straight across

DIVIDING RATIONAL NUMBERS

SIMPLIFYING ALGEBRAIC EXPRESSIONS

5

105 x

Reduce - CancelCan’t “cancel” unless able to do so in every term.

1

1

2

1

2x

2x

DIVIDING RATIONAL NUMBERS

SIMPLIFYING ALGEBRAIC EXPRESSIONS

8

128 y

Reduce - CancelCan’t “cancel” unless able to do so in every term.

2

2

3

2

32 y

DIVIDING RATIONAL NUMBERS

SIMPLIFYING ALGEBRAIC EXPRESSIONS

12

612

m

Reduce - CancelCan’t “cancel” unless able to do so in every term.

-2

2

-1

2

12

m

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