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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
