bellringer – name the property
DESCRIPTION
Bellringer – Name the property. (9 + 8) + 7 = 9 + (8 + 7). The Associative Property of Addition. 12 + 0 = 12. The Identity Property of Addition. 9 + 7 = 7 + 9. The Commutative Property of Addition. Go Over Homework. Textbook page 10-11, problem 8-40 even show all your work - PowerPoint PPT PresentationTRANSCRIPT
Bellringer – Name the property
(9 + 8) + 7 = 9 + (8 + 7) The Associative Property of Addition
12 + 0 = 12 The Identity Property of
Addition9 + 7 = 7 + 9
The Commutative Property of Addition
Go Over Homework
Textbook page 10-11, problem 8-40
even show all your work
Skip Problem #34
Multiply DecimalsChapter 1, Section 3
Four Properties of MultiplicationFour Properties of Multiplication1. Commutative2. Associative3. Identity4. Zero Property
Communative Property of MultiplicationCommunative Property of Multiplication
Commuter A
Commuter B
Commuter A
Commuter B
A x B = B x A.
Remember… commute means to change.
The Commutative PropertyThe Commutative Property
A x B = B x AA x B = B x A
Commutative Property of
Multiplication
Changing the order of the factors does not change the product
A x B = B x A 1 x 2 x 3 = 3 x 1 x 2
4 x 5 x 6 = 5 x 6 x 4
Four Properties of MultiplicationFour Properties of Multiplication1. Commutative2. Associative3. Identity4. Zero Property
The Associative PropertyThe Associative Property
(A x B) x C = A x (B x C)
(A x B) x C = A x (B x C)
A C
B
A C
B
THEN THEN
The parentheses identify which two associates talked first.
Associative Property of
Multiplication
Changing the grouping of the factors does not change the product .
(1 x 2) x 3 = 1 x ( 2 x 3)
(4 x 5) x 6 = 4 x ( 5 x 6 )
(A x B) x C = A x ( B x C)
Four Properties of MultiplicationFour Properties of Multiplication1. Commutative2. Associative3. Identity4. Zero Property
Identity Property of MultiplicationIdentity Property of Multiplication
A x 1 = A
x 1 =
Identity Property of Multiplication
The product of one and anything is anything
1 x 3 = 3
18 x 1 = 18
1 x C = C
Four Properties of MultiplicationFour Properties of Multiplication1. Commutative2. Associative3. Identity4. Zero Property
Zero Property of MultiplicationZero Property of Multiplication
A x 0 = 0
x 0 = 0
Zero Property of Multiplication
The product of zero and anything is zero
3 x 0 = 0
18 x 0 =0
0 x C = 0
Let’s practice !Let’s practice !
Look at the problem.
Identify which property it represents.
(9 x 8) x 7 = 9 x (8 x 7)
The Associative Property
12 x 0 = 0
Zero Property
3 x1 = 3 The Identity Property
9 x 7 = 7 x 9
The Commutative Property
4 x1 = 4Identity Property
Numbers change places.
(4 x 3) x 2 = 4 x (3 x 2)
The Associative Property
It has parentheses!
a x b = b x aThe Commutative Property
Moving numbers!
a x 0 = 0 Zero Property
A
(a x b) x c = a x (b x c) The Associative Property
Parentheses!
C
B
1. Write the Problem
4 . 32x 0.012
*** Place values do NOT need to line up, but digits do!!!
Multiplying Decimals - Steps
2. Pretend decimals are not there!
4 . 32x 0.012
Multiplying Decimals - Steps
3. Multiply
4 . 32x 0.012 864+ 432000000
05184
Multiplying Decimals - Steps
4. Count total number of places behind ALL Decimals
4 . 32x 0.012 864+ 432000000
05184
2 places
3 places
5 total places!!
Multiplying Decimals - Steps
5. Place decimal that many places left.
. 05184
4 . 32x 0.012 864+ 432000000
05184
Multiplying Decimals - Steps
Textbook pg. 16 #1-10 & 20 together
3.41
Homework Time
Textbook page 16, problem 12-30 even show all your work
12- 18 do not estimate, give exact answer
30 show work (not extra credit)