Warm - Up

999 + 364 = (1000 +364) - 1 = 1363Use a similar problem-solving strategy to compute the following. Show all of your work.

1. 998 + 6542. 500-2993. 999+998

Finished early?• Take out a colored writing

utensil and homework. Staple homework in order.

• Help a neighbor with these problems

1.2 & 1.4 Homework CheckUsing your colored writing utensil, box in the following

two problems to be graded by a neighbor.

1.2 # 57) 15 – b, b = 7

1.4 # 27) 33 – 8 * 3 ÷12

Mathematical Properties

1.7-1.8

Pre-Algebra PropertiesProperty

1. Commutative Property of

Addition

2. Commutative Property of

Multiplication

In words…You can add terms in any

order

You can multiply terms in any

order

In math…2+3 = 3+2

3 ∙ 7 = 7 ∙ 3

Pre-Algebra PropertiesProperty

3. Associative Property of

Addition

4. Associative Property of

Multiplication

In words…Changing the grouping

of terms does not change the sum

Changing the grouping of terms does not

change the product

In math…(9+5)+6 =

9+(5+6)

(5∙10) ∙ 3 = 5 ∙(10 ∙ 3)

Pre-Algebra Properties

Property5. Distributive

Property

In words…Multiply a number in

front of parentheses to all terms inside the

parentheses

In math…5(x+2)

=5∙x + 5∙2=5x+10

Name this property!

7 ∙ 8 = 8 ∙ 7

Commutative Property of Multiplication

Name this property!

(2+3)+4 = 2+(3+4)

Associative Property of Addition

Name this property!

2(x+3) = 2x + 6

Distributive Property

Name this property!

(2)(3)(4) = (3)(2)(4)

Commutative Property of Multiplication

Name this property!

(2+3) + 4 = (3+2) + 4Commutative Property of Addition

Using the Distributive Property

Now let’s try to reverse the distributive property!

5n + 15 = ___ ( ___ + ___)

Think! What number was distributed to give us 5n and 15?

5 n 3

Using the Distributive Property

Now let’s try to reverse the distributive property!

7 + 14x = ___ ( ___ + ___)

Think! What number was distributed to give us 7 and 14x?

7 1 2x